term% ls -F
term% cat index.txt
========= THIS IS THE JARGON FILE, VERSION 2.3.1 03 JAN 1991  =================


This document is a collection of slang terms used by various
subcultures of computer hackers.  Though some technical material is
included for background and flavor, it is not a technical dictionary;
what we describe here is the language hackers use among themselves for
fun and social communication within their communities.

Though the format is that of a reference, it is also intended that
the material be enjoyable to browse or read straight through.  Even a
complete outsider should find at least a chuckle on nearly every page,
and much that is amusingly thought-provoking.

The `hacker culture' is actually a loosely networked collection of
subcultures that is nevertheless conscious of some important shared
experiences, shared roots, and shared values.  It has its own myths,
heroes, villains, folk epics, in-jokes, taboos and dreams.  Because
hackers as a group are particularly creative people who define
themselves partly by rejection of `normal' values and working habits,
it has unusually rich and conscious traditions for an intentional
culture less than thirty-five years old.

Hackers, as a rule, love word-play and are very conscious in their use
of language.  Thus, a compilation of their slang is a particularly
effective window into their culture --- and, in fact, this one is the
latest version of an evolving compilation called the `Jargon File'
maintained by hackers themselves for over fifteen years.  This one
(like its ancestors) is primarily a lexicon, but also includes `topic
entries' which collect background or sidelight information on hacker
culture that would be awkward to try and subsume under a single term.

A selection of longer items of hacker folklore and humor are included
in appendix A.  The `outside' reader's attention is particularly
directed to Appendix B, the Portrait of J. Random Hacker.  Appendix C
is a bibliography of non-technical works which have either influenced
or described the hacker culture.

Because hackerdom is an intentional culture (one which each individual
must choose consciously to join), one should not be surprised that the
line between description and influence can become more than a little
blurred.  Earlier Jargon File versions have played a central role in
spreading hacker language and the culture that goes with it to
successively larger populations, and we hope and expect that this one
will do likewise.

Revision History

The original `jargon file' (hereafter referred to as `jargon-1') was a
collection of hacker slang from technical cultures including the MIT
AI Lab, the Stanford AI lab, the old ARPANET AI/LISP/PDP-10
communities, Carnegie-Mellon University, and Worcester Polytechnic
Institute.  Some entries dated back to the early 1970s. It was
compiled by Raphael Finkel, Don Woods, Mark Crispin, and Guy L. Steele
Jr., and last revised about 1983.  Its revisions are all un-numbered
and may be collectively considered `Version 1'.

A late version of jargon-1, expanded with commentary for the mass
market, was edited by by Guy L. Steele into a book published in 1983
as `The Hacker's Dictionary' (Harper & Row CN 1082, ISBN
0-06-091082-8).  The other jargon-1 editors (Raphael Finkel, Don Woods
and Mark Crispin) contributed to the revision, as did also Richard M.
Stallman and Geoff Goodfellow.  This book is hereafter referred to as
`Steele-1983'.  It is now out of print.

This version contains nearly the entire text of a late version of
jargon-1 (a few obsolescent PDP-10-related entries have been dropped
following careful consultation with the editors of Steele-1983).  It
merges in about about 80% of the Steele-1983 text, omitting some
framing material and a very few entries introduced in Steele-1983
which are now also obsolescent.

This new version casts a wider net than the old jargon file; its aim
is to cover not just AI but all the technical computing cultures
wherein the true hacker-nature is manifested.  More than half of the
entries now derive from USENET and represent slang now current in the
C and UNIX communities.

The present maintainer of the jargon file is Eric S. Raymond
( with some assistance from Guy L. Steele
(; these are the persons primarily reflected in the
File's editorial `we', though we take pleasure in acknowledging the
special contribution of the other coauthors of Steele-1983.  Please
email all additions, corrections and correspondence relating to the
jargon file to (UUCP-only sites without
connections to an autorouting smart site can use

(Warning: other email addresses appear in this file *but are not
guaranteed to be correct* later than the revision date on the first
line.  *Don't* email us if an attempt to reach your idol bounces
--- we have no magic way of checking addresses or looking up people)

Some snapshot of this on-line version will become the main text of a
`New Hacker's Dictionary' possibly as early as Fall 1991.  The
maintainers are committed to updating the on-line version of the
jargon file through and beyond paper publication, and will continue to
make it available to archives and public-access sites as a trust of
the hacker community.

Here is a chronology of the recent on-line revisions:

Version 2.1.1, Jun 12 1990: the jargon file comes alive again after a
seven-year hiatus. Reorganization and massive additions were by Eric
S. Raymond, approved by Guy Steele.  Many items of UNIX, C, USENET and
microcomputer-based slang were added at that time (as well as The
Untimely Demise of Mabel The Monkey).  Some obsolescent usages (mostly
PDP-10 derived) were moved to appendix B.

Version 2.1.5, Nov 28 1990: changes and additions by ESR in response to
numerous USENET submissions and comment from the First Edition coauthors.
The bibliography (Appendix C) was also appended.

Version 2.2.1, Dec 15 1990: most of the contents of the 1983 paper
edition edited by Guy Steele was merged in.  Many more USENET
submissions added, including the International Style and

Version 2.3.1, Jan 03 1991: the great format change --- case is no
longer smashed in lexicon keys and cross-references.  A very few
entries from jargon-1 which were basically straight tech-speak were
deleted; this enabled the rest of Appendix B to be merged back into
main text and the appendix replaced with the Portrait of J. Random
Hacker. More USENET submissions were added.

Version numbering: Read versions as <major>.<minor>.<revision>.  Major
version 1 is reserved for the `old' (ITS) Jargon File, jargon-1.  Major
version 2 encompasses revisions by ESR with assistance from GLS.  Someday,
the next maintainer will take over and spawn `version 3'. In general, later
versions will either completely obsolesce or incorporate earlier versions,
so there is generally no point in keeping old versions around.

Our thanks to the other co-authors of Steele-1983 for oveersight and
assistance; also to all the USENETters who contributed entries and
encouragement.  Special thanks go to our Scandinavian correspondent
Per Lindberg (, author of the remarkable Swedish
language 'zine `Hackerbladet', for bringing FOO! comics to our
attention and smuggling the IBM hacker underground's own baby jargon
file out to us.  Also, much gratitude to ace hacker/linguist Joe Keane
( for helping us improve the pronunciation guides;
and to Maarten Litmath for generously allowing the inclusion of the
ASCII pronunciation guide he formerly maintained.  Finally, Mark
Brader ( submitted many, many K of thoughtful comments
and did yeoman service in catching typos and minor usage bobbles.

Format For New Entries

Try to conform to the format already being used --- definitions and
cross-references in angle brackets, pronunciations in slashes,
etymologies in square brackets, single-space after definition numbers
and word classes, etc.  Stick to the standard ASCII character set (no
high-half characters or [nt]roff/TeX/Scribe escapes), as one of the
versions generated from the master file is an info document that has
to be viewable on a character tty.

Please note that as of 2.3.1 the preferred format has changed rather
dramatically; please *don't* all-caps your entry keys any more.
Besides preserving case information, this enables the maintainers to
process the File into a rather spiffy [nt]roff document with font
switches via an almost trivial lex(1) program.  This is all in aid of
preventing the freely-available on-line document and the book from

We are looking to expand the file's range of technical specialties covered.
There are doubtless rich veins of jargon yet untapped in the scientific
computing, graphics, and networking hacker communities; also in numerical
analysis, computer architectures and VLSI design, language design, and many
other related fields.  Send us your slang!

We are *not* interested in straight technical terms explained by
textbooks or technical dictionaries unless an entry illuminates
"underground" meanings or aspects not covered by official histories.
We are also not interested in "joke" entries --- there is a lot of
humor in the file but it must flow naturally out of the explanations
of what hackers do and how they think.

It is OK to submit items of slang you have originated if they have spread
to the point of being used by people who are not personally acquainted with
you.  We prefer items to be attested by independent submission from two
different sites.

A few new definitions attached to entries are marked [proposed].
These are usually generalizations suggested by editors or USENET
respondents in the process of commenting to previous definitions of
those entries.  These are *not* represented as established

The jargon file will be regularly maintained and re-posted from now on and
will include a version number.  Read it, pass it around, contribute --- this
is *your* monument!

Jargon Construction

There are some standard methods of jargonification which became
established quite early (i.e. before 1970), spreading from such
sources as the MIT Model Railroad Club, the PDP-1 SPACEWAR hackers and
John McCarthy's original crew of LISPers.  These include:

Verb doubling: a standard construction is to double a verb and use it as a
comment on what the implied subject does.  Often used to terminate a
conversation.  Typical examples involve <win>, <lose>, <hack>, <flame>,
<barf>, <chomp>:

     "The disk heads just crashed."  "Lose, lose."
     "Mostly he just talked about his @#!!$% crock.  Flame, flame."
     "Boy, what a bagbiter!  Chomp, chomp!"

Some verb-doubled constructions have special meanings not immediately
obvious from the verb.  These have their own listings in the lexicon.

Soundalike slang: Phonetic distortions of a phrase intended to produce the
effect of a pun or wordplay.  Not really similar to the Cockney rhyming
slang it has been compared to in the past, because Cockney substitutions
are opaque whereas hacker rhyming slang is intentionally transparent.
Often made up on the spur of the moment.  Standard examples:

     Boston Globe => Boston Glob
     Herald American => Horrid (or Harried) American
     New York Times => New York Slime
     Prime Time => Slime Time
     Data General => Dirty Genitals
     Government Property - Do Not Duplicate (seen on keys)
             => Government Duplicity - Do Not Propagate
     for historical reasons => for hysterical raisins

Often the substitution will be made in such a way as to slip in
a standard jargon word:

     Dr. Dobb's Journal => Dr. Frob's Journal
     Margaret Jacks Hall => Marginal Hacks Hall

The -P convention: turning a word into a question by appending the
syllable "P"; from the LISP convention of appending the letter "P"
to denote a predicate (a Boolean-valued function).   The question
should expect a yes/no answer, though it needn't.  (See T and NIL.)

     At dinnertime:
            Q: "Foodp?"
            A: "Yeah, I'm pretty hungry." or "T!"

            Q: "State-of-the-world-P?"
            A: (Straight) "I'm about to go home."
            A: (Humorous) "Yes, the world has a state."

     On the phone to Florida:
            Q: "State-p Florida?"
            A: "Been reading JARGON.TXT again, eh?"

[One of the best of these is a Gosperism (i.e., due to Bill
Gosper).  When we were at a Chinese restaurant, he wanted to know
whether someone would like to share with him a two-person-sized
bowl of soup.  His inquiry was: "Split-p soup?" --GLS]

Overgeneralization: A very conspicuous feature of hackerspeak is the
frequency with which names of program tools, command language
primitives, and even assembler opcodes are applied to contexts outside
of computing wherever hackers find amusing analogies to them.  Thus,
(to cite one of the best-known examples) UNIX hackers often <grep> for
things rather than *searching* for them.  Many of the lexicon
entries are generalizations of exactly this kind.

Hackers enjoy overgeneralization on the grammatical level as well.
Many hackers love to take various words and add the wrong endings to
them to make nouns and verbs, often by extending a standard rule to
nonuniform cases.  For example, because

     porous => porosity
     generous => generosity

hackers happily generalize:

     mysterious => mysteriosity
     ferrous => ferrocity

Also, note that all nouns can be verbed.  e.g.: "All nouns can be
verbed", "I'll mouse it up", "Hang on while I clipboard it over",
"I'm grepping the files".  English as a whole is already heading in
this direction (towards pure-positional grammar like Chinese);
hackers are simply a bit ahead of the curve.

Similarly, all verbs can be nouned.  Thus:

     win -> winnitude, winnage
     disgust -> disgustitude
     hack -> hackification

Finally, note the prevalence of certain kinds of nonstandard plural
forms.  Anything ending in x may form plurals in -xen (see <VAXen> and
<boxen> in the main text). Even words ending in phonetic /k/ alone are
sometimes treated this way; ex. `soxen' for a bunch of socks.  Other
funny plurals are `frobbotzim' for the plural of <frobbotz> (see main
text) and `Unices' and `Tenices' (rather than `Unixes' and `Tenexes';
see <UNIX>, <TENEX> in main text). But note that `Unixen' and `Tenexen'
are *never* used; it has been suggested that this is because
-ix and -ex are latin singular endings that "attract" as Latin

The pattern here, as with other hackish grammatical quirks, is
generalization of an inflectional rule which (in English) is either
an import or a fossil (such as Hebrew plural in `-im', or the
Anglo-Saxon plural in `en') to cases where it isn't normally
considered to apply.

This is not `poor grammar', as hackers are generally quite well
aware of what they are doing when they distort the language.  It is
grammatical creativity, a form of playfulness.

Spoken inarticulations: Words such as "mumble", "sigh", and
"groan" are spoken in places where their referent might more
naturally be used.  It has been suggested that this usage derives from
the impossibility of representing such noises on a comm link or in
email.  Another expression sometimes heard is "complain!", meaning
"I have a complaint!"

Of the five listed constructions, verb doubling, peculiar noun
formations, and (especially!) spoken inarticulations have become quite
general; but rhyming slang is still largely confined to MIT and other
large universities, and the P convention is found only where LISPers

Finally, note that many words in hacker jargon have to be
understood as members of sets of comparatives.  This is especially
true of the adjectives and nouns used to describe the beauty and
functional quality of code.  Here is an approximately correct


The last is spoken of as a mythical absolute, approximated but never
actually attained.  Coinages for describing <lossage> seem to call
forth the very finest in hackish linguistic inventiveness; it has been
truly said that "<Computer geeks> have more words for equipment
failures than Inuits have for snow".

Hacker Speech Style

Features extremely precise diction, careful word choice, a
relatively large working vocabulary, and relatively little use of
contractions or "street slang".  Dry humor, irony, puns, and a
mildly flippant attitude are highly valued --- but an underlying
seriousness and intelligence is essential.  One should use just
enough jargon to communicate precisely and identify oneself as "in
the culture"; overuse of jargon or a breathless, excessively
gung-ho attitude are considered tacky and the mark of a loser.

This speech style is a variety of the precisionist English normally
spoken by scientists, design engineers, and academics in technical
fields.  Unlike the jargon construction methods it is fairly constant
throughout hackerdom.

It has been observed that many hackers are confused by negative
questions --- or, at least, the  people they're talking to are often
confused by the sense of their answers.  The problem is that they've
done so much coding that distinguishes between

     if (going) {


     if (!going) {

that when they parse the question "Aren't you going?" it seems to be
asking the opposite question from "Are you going?", and so merits an
answer in the opposite sense.  This confuses English-speaking
non-hackers because they were taught to answer as though the negative
part weren't there (in some other languages, including Chinese and
Japanese, the hackish interpretation is standard and the problem
wouldn't arise).  Hackers often find themselves wishing for a word
like French "si" with which one could unambiguously answer "yes"
to a negative question.

For similar reasons, English-speaking hackers almost never use a
double negative even if they live in a region where colloquial usage
allows it.  The thought of uttering something that logically ought to
be an affirmative knowing it will be mis-parsed as a negative tends to
disturb them. 

Hacker Writing Style

Hackers tend to use quotes as balanced delimiters like parens, much to
the dismay of American editors.  Thus, if "Jim is going" is a
phrase, and so is "Bill runs" and "Spock groks", then hackers
generally prefer to write: "Jim is going", "Bill runs", and
"Spock groks".  This is incorrect according to standard American
usage (which would put the continuation commas and the final period
inside the string quotes) but it is counter-intuitive to hackers to
mutilate literal strings with characters that don't belong in them.
The Jargon File follows hackish usage fairly consistently throughout.

Interestingly, this is now preferred practice in Great Britain, though
the older style (which became established for typographical reasons
having to do with the aesthetics of comma and quotes in typeset text)
is still accepted there.  Hart's Rules and the Oxford Dictionary for
Writers and Editors call it "new" or "logical" style quoting.

Hackers have also developed a number of punctuation and emphasis
conventions adapted to single-font all-ASCII communications links, and
these are occasionally carried over into written documents even when
normal means of font changes, underlining and the like are available.

One of these is that TEXT IN ALL CAPS IS INTERPRETED AS "LOUD", and
this becomes such a synesthetic reflex that a person who goes to
caps-lock while in <talk mode> (see main text) may be asked to "stop
shouting, please, you're hurting my ears!".

Also, it is common to use bracketing with asterisks to signify
emphasis, as in "What the *hell*?".  An alternative form uses paired
slash and backslash: "What the \hell/?".  The latter is never used
in text documents, as many formatters treat backslash as an <escape>
and may do inappropriate things with the following text.

Two asterisks in a row, on the other hand, are a shorthand for
exponentiation (this derives from FORTRAN).  Thus one might write "2
** 8 = 256".

Another notation for exponentiation one sees more frequently uses the
caret (^, ASCII 1011110); one might write instead "2^8 = 256".  This
goes all the way back to Algol-60, which used the archaic ASCII
`up-arrow' that later became caret; this was picked up by Kemeny &
Hall's original BASIC, which in turn influenced the design of the
bc(1) and dc(1) UNIX tools that have probably done most to reinforce
the convention on USENET.  The notation is mildly confusing to C
programmers, because `^' means logical XOR in C.  Despite this, it was
favored 3-1 over ** in a late-1990 snapshot of USENET.  It is used
consistently in this text.

Underlining is often suggested by substituting underscores for spaces
and prepending and appending one underscore to the underlined phrase.
Example: "It is often alleged that Haldeman wrote _The_Forever_War_
in response to Robert Heinlein's earlier _Starship_Troopers_"

On USENET and in the MUD world (see <MUD> in main text) common C
boolean operators (|, !, ==, !=, >, <) are often combined with English
by analogy with mainstream usage of &.  The use of prefix `!' as a
loose synonym for `not-' or `no-' is particularly common; thus,
`!clue' is read `no-clue' or `clueless'.

Another habit is that of using enclosure to genericize a term; this
derives from conventions used in <BNF>.  Uses like the following are

     So this <ethnic> walks into a bar one day, and...

In flat-ASCII renderings of the Jargon File, you will see <> used in
exactly this way to bracket words which themselves have entries in the
File.  This isn't done all the time for every such word, but it is
done everywhere that the reader needs specially to be aware that the
term has a jargon meaning and might wish to refer to its entry.

One quirk that shows up frequently in the email style of UNIX hackers
in particular is a tendency for some things which are normally
all-lowercase (including usernames and the names of commands and C
routines) to remain uncapitalized even when they occur at the
beginning of sentences.  It is clear that for many hackers, the case of
such identifiers becomes a part of their internal representation and
cannot be overridden without mental effort (an appropriate reflex
because UNIX and C both distinguish cases and confusing them can lead
to lossage). The *rest* of us simply avoid using these
constructions at the beginning of sentences.

Finally, it should be noted that hackers exhibit much less reluctance
to use multiply-nested parentheses than is normal in English.  Partly
this is almost certainly due to influence from LISP ((which uses
deeply nested parentheses (like this) in its syntax) (a lot (see?))),
but it has also been suggested that a more basic hacker trait of
enjoying playing with complexity and pushing systems to their limits
is in operation.

International Style

Although the Jargon File remains primarily a lexicon of hacker
usage in American English, we have made some effort to get input from
abroad.  Though the hacker-speak of other languages often uses
translations of English slang (often as transmitted to them by earlier
Jargon File versions!) the local variations are interesting, and
knowledge of them may be of some use to traveling hackers.

There are some references to `Commonwealth English'. These are
intended to describe some variations in hacker usage as reported in
the English spoken in Great Britain and the Commonwealth (Canada,
Australia, India etc., though Canada is heavily influenced by American
usage) There is also an entry on COMMONWEALTH HACKISH, which see.

Hackers in Western Europe and (especially) Scandinavia are reported
to often use a mixture of English and their native languages for
technical conversation.  Occasionally they develop idioms in their
English usage which are influenced by their native-language styles.
Some of these are reported here.

A note or two on hackish usages in Russian have been added where they
are parallel with and comprehensible to English-speakers. 

UNIX Conventions

References such as `malloc(3)' and `patch(1)' are to UNIX
facilities (some of which, such as patch(1), are actually freeware
distributed over USENET).  The UNIX manuals use `foo(n)' to refer
to item foo in section (n) of the manual, where n=1 is utilities, n=2
is system calls, n=3 is C library routines, n=6 is games, and n=8
(where present) is system administration utilities.  Sections 4, 5,
and 7 have changed roles frequently and in any case are not referred
to from any of the entries.

Pronunciation Guide

Pronunciation keys are provided in the jargon listing for all
entries which are neither dictionary words pronounced as in standard
English nor obvious compounds of same.  Slashes bracket a phonetic
pronunciation to be interpreted using the following conventions:

  1. Syllables are hyphen-separated, except that an apostrophe
     or back-apostrophe follows each accented syllable (the
     back apostrophe marks a secondary accent in some words of
     four or more syllables).

  2. Consonants are pronounced as in American English.  The letter
     "g" is always hard (as in "got" rather than "giant");
     "ch" is soft ("church" rather than "chemist").  The letter
     "j" is the sound that occurs twice in "judge".  The letter
     "s" is always as in "pass", never a z sound (but it is
     sometimes doubled at the end of syllables to emphasize this).
     The digraph `dh' is the th of `these clothes', not of `thick'.
     The digraph `kh' is the guttural of `loch' or `l'chaim'.

  3. Vowels are represented as follows:

          a	back, that
          ah	father, palm
          ar	far, mark
          aw	flaw, caught
          ay	bake, rain
          e	less, men
          ee	easy, ski
          eir	their, software
          i	trip, hit
          ie	life, sky
          o	cot, top
          oh	flow, sew
          oo	loot, through
          or	more, door
          ow	out, how
          oy	boy, coin
          uh	but, some
          u	put, foot
          y	yet
          yoo	few
          [y]oo	oo with optional fronting as in `news' (noos or nyoos)

An at-sign is used for the "schwa" sound of unstressed or occluded
vowels (the one that is often written with an upside-down "e").  The
schwa vowel is omitted in syllables containing vocalic r, l, m or n;
that is, "kitten" and "color" would be rendered /kit'n/ and
/kul'r/, not /kit'@n/ and /kul'@r/.

Entries are sorted in case-blind ASCII collation order (rather than
the letter-by-letter order ignoring interword spacing common in
mainstream dictionaries).  The case-blindness is a feature, not
a bug.

The Jargon Lexicon

                                {=   =}

<@-party> /at-part'ee/ n. (also "@-sign party" /at-sien par'tee/)
   Semi-closed parties thrown at SF conventions (esp.  the annual
   Worldcon) for hackers; one must have a <network address> to get in,
   or at least be in company with someone who does.  One of the most
   reliable opportunities for hackers to meet face to face with people
   who might otherwise be represented by mere phosphor dots on their
   screens.  Compare <boink>.

<@Begin> [primarily CMU] n. SCRIBE equivalent of <\Begin>.

<(TM)> [USENET] ASCII rendition of the trademark symbol, appended to
   phrases that the author feels should be recorded for posterity,
   perhaps in the Jargon File.  Sometimes used ironically as a form of
   protest against the recent spate of software and algorithm patents,
   and "look and feel" lawsuits.

</dev/null> [from the UNIX null device, used as a data sink] n.  A
   notional `black hole' in any information space being discussed,
   used or referred to.  A controversial posting, for example, might
   end "Kudos to, flames to /dev/null".  See
   <bit bucket>, <null device>.

<2 infix> n. In translation software written by hackers, infix 2 often
   represents the syllable "to" with the connotation "translate
   to"; as in dvi2ps (DVI to PostScript), int2string (integer to
   string) and texi2roff (Texinfo to [nt]roff).

<\Begin> with \End, used humorously in writing to
   indicate a context or to remark on the surrounded text.  From the
   LaTex command of the same name.  For example:

     Predicate logic is the only good programming language.
     Anyone who would use anything else is an idiot.  Also,
     computers should be tredecimal instead of binary.

   The Scribe users at CMU and elswhere used to use @Begin/@End in
   an identical way.  On USENET, this construct would more frequently
   be rendered as "<FLAME ON>" and "<FLAME OFF>".

                                {= A =}

<ACK> /ak/ interj. 1. [from the ASCII mnemonic for 0000110]
   Acknowledge.  Used to register one's presence (compare mainstream
   "Yo!").  An appropriate response to <ping> or <ENQ>. 2. [prob.
   from the Bloom County comic strip] An exclamation of surprised
   disgust, esp. in "Oop ack!".  Semi-humorous.  3. Used to politely
   interrupt someone to tell them you understand their point.  See
   <NAK>.  Thus, for example, you might cut off an overly long
   explanation with "Ack. Ack. Ack.  I get it now".  See also <NAK>.

   There is also a usage "ACK?" (from sense #1) meaning "Are you
   there?", often used in email when earlier mail has produced no
   reply, or during a lull in <talk mode> to see if the person has
   gone away (the standard humorous response is of course <NAK>
   (sense #2), i.e. "I'm not here").

<adger> /adj'r/ [UCLA] v. To make a bonehead move that could have been
   foreseen with a slight amount of mental effort.  E.g., "He started
   removing files and promptly adgered the whole project."  Compare
   <dumbass attack>.

<ad-hockery> /ad-hok'@r-ee/ [Purdue] n. 1. Gratuitous assumptions
   made inside certain programs, esp. expert systems, which lead to
   the appearance of semi-intelligent behavior, but are in fact
   entirely arbitrary.  2. Special-case code to cope with some awkward
   input which would otherwise cause a program to <choke>, presuming
   normal inputs are dealt with in some cleaner and more regular way.

<ADVENT> /ad'vent/ n. The prototypical computer adventure game, first
   implemented on the <PDP-10> by Will Crowther as an attempt at
   computer-refereed fantasy gaming, and expanded into a
   puzzle-oriented game by Don Woods.  Now better known as Adventure,
   but the <TOPS-10> operating system only permitted 6-letter

   This game defined the terse, dryly humorous style now expected in
   text adventure games, and popularized several tag lines that have
   become fixtures of hacker-speak. "A huge green fierce snake bars
   the way!"  "I see no X here." (for X some noun). "You are in a
   maze of twisty little passages, all alike".  The "magic words"
   <xyzzy> and <plugh> also derive from this game.

   Crowther, by the way, participated in the exploration of the
   Mammoth/Flint Ridge cave system; it actually *has* a `Colossal
   Cave' and a `Bedquilt' as in the game, and the `Y2' that also turns
   up is cavers' jargon for a map reference to a secondary entrance.

<AI koans> pl.n. A series of pastiches of Zen teaching riddles created
   at the MIT AI Lab around various major figures of the Lab's
   culture.  A selection are included in Appendix A. See also <ha ha
   only serious> and <HUMOR, HACKER>.

<aliasing bug> [C programmers] n. A class of subtle programming errors
   which can arise in code that does dynamic allocation via `malloc(3)'.
   If more than one pointer addresses (`aliases for') a given hunk of
   storage, it may happen that the storage is freed through one alias
   and then referenced through another, leading to subtle (and
   possibly intermittent) lossage depending on the state and the
   allocation history of the malloc <arena>.  Avoidable by use of
   allocation strategies that never alias allocated core.  Also called
   a <stale pointer bug>.  See also <precedence lossage>, <smash the
   stack>, <fandango on core>, <memory leak>, <overrun screw>, <spam>.

<ALT> [PDP-10] n.obs. Alternate name for the ASCII ESC character,
   after the keycap labeling on some older terminals.  Also
   "ALT-MODE".  This character was almost never pronounced
   "escape" on an ITS system, in TECO, or under TOPS-10 -- always
   ALT, as in "type ALT ALT to end a TECO command" or "ALT U onto
   the system" (for "log onto the [ITS] system").  This was
   probably because ALT is more convenient to say than "escape",
   especially when followed by another ALT or a character (or another
   ALT *and* a charcater, for that matter!).

<alt bit> /ahlt bit/ [from alternate] adj.  See <meta bit>.

<Aluminum Book> [MIT] n. `Common Lisp: The Language', by Guy L.
   Steele Jr., Digital Press, first edition, 1984, second edition
   1990.  Strictly speaking, only the first edition is the aluminum
   book, since the second edition has a yuccky pale green cover.  See
   also <Blue Book>, <Red Book>, <Green Book>, <Silver Book>, <Purple
   Book>, <Orange Book>, <White Book>, <Pink-Shirt Book>, <Dragon

<amoeba> /@'mee-b@/ n. Humorous term for the Commodore Amiga
   personal computer.

<amp off> [Purdue] v. To run in <background>.  From the UNIX shell `&'

<angle brackets> [primarily MIT] n. Either of the characters "<" and
   ">" (ASCII less-than or greater-than signs).  The <Real World>
   angle bracket used by typographers is actually taller than a
   less-than or greater-than sign.  See <broket>, <ASCII>.

<AOS> /aus/ (East coast), /ay-ahs/ (West coast) [based on a PDP-10
   increment instruction] v.,obs. 1. To increase the amount of
   something.  "Aos the campfire."  Usage: considered silly, and now
   obsolescent.  See <SOS>.  Now largely supplanted by <bump>.  2. A
   crufty <Multics>-derived OS supported at one time by Data General.

<app> /ap/ n. Short for `application program', as opposed to a systems
   program.  What systems vendors are forever chasing developers to do
   for their environments so they can sell more boxes.  Hackers tend
   not to think of the things they themselves run as apps; thus, in
   hacker parlance the term excludes compilers, program editors,
   games, and messaging systems, though a user would consider all
   those apps.  Oppose <tool>, <operating system>.

<arena> [UNIX] n. The area of memory attached to a process by `brk(2)'
   and `sbrk(2)' and used by `malloc(3)' as dynamic storage.  So named
   from a semi-mythical `malloc: corrupt arena' message supposedly
   emitted when some early versions became terminally confused.  See
   <overrun screw>, <aliasing bug>, <memory leak>, <smash the stack>.

<arg> /arg/ n. Abbreviation for "argument" (to a function), used so
   often as to have become a new word (like "piano" from
   "pianoforte").  "The sine function takes one arg, but the
   arc-tangent function can take either one or two args".  Compare
   <param>, <var>.

<asbestos cork award> n.  Once, long ago at MIT, there was a <flamer>
   so consistently obnoxious that another hacker designed, had made,
   and distributed posters announcing that said flamer had been
   recognized by the "asbestos cork award".  Persons in any doubt as
   to the intended application of the cork should consult the
   etymology under <flamer>.  Since then, it is agreed that only a
   select few have risen to the heights of bombast required to earn
   this dubious dignity --- but there's no agreement on *which*

<asbestos longjohns> n. Metaphoric garments often donned by <USENET>
   posters just before emitting a remark they expect will elicit
   <flamage>.  Also "asbestos underwear", "asbestos overcoat",

<ASCII> [American Standard Code for Information Interchange] /as'kee/
   n. Common slang names for ASCII characters are collected here.  See
   individual entries for <bang>, <close>, <excl>, <open>, <ques>,
   <semi>, <shriek>, <splat>, <twiddle>, <what>, <wow>, and <Yu-Shiang
   whole fish>.  This list derives from revision 2.2 of the USENET
   ASCII pronunciation guide.  Single characters are listed in ASCII
   order, character pairs are sorted in by first member.  For each
   character, "official" names appear first, then others in order of
   popularity (more or less).

     exclamation point, exclamation, bang, factorial, excl,
     ball-bat, pling, smash, shriek, cuss, wow, hey, wham

     double quote, quote, dirk, literal mark, rabbit ears

     number sign, sharp, crunch, mesh, hex, hash, flash, grid,
     pig-pen, tictactoe, scratchmark, octothorpe, thud

     dollar sign, currency symbol, buck, cash, string (from
     BASIC), escape (from <TOPS-10>), ding, big-money, cache

     percent sign, percent, mod, double-oh-seven

     ampersand, amper, and, address (from C), andpersand

     apostrophe, single quote, quote, prime, tick, irk, pop,

     open/close parenthesis, left/right parenthesis,
     paren/thesis, lparen/rparen, parenthisey, unparenthisey,
     open/close round bracket, ears, so/already, wax/wane

     asterisk, star, splat, wildcard, gear, dingle, mult

     plus sign, plus, add, cross, intersection

     comma, tail

     hyphen, dash, minus sign, worm

     period, dot, decimal point, radix point, point, full stop,

     virgule, slash, stroke, slant, diagonal, solidus, over, slat


     semicolon, semi

     angle brackets, brokets, left/right angle, less/greater
     than, read from/write to, from/into, from/toward, in/out,
     comesfrom/ gozinta (all from UNIX), funnel, crunch/zap,

     equal sign, equals, quadrathorp, gets, half-mesh

     question mark, query, whatmark, what, wildchar, ques, huh,

     at sign, at, each, vortex, whorl, whirlpool, cyclone, snail,
     ape, cat

     vee, book

     square brackets, left/right bracket, bracket/unbracket,
     bra/ket, square/unsquare, U turns

     reversed virgule, backslash, bash, backslant, backwhack,
     backslat, escape (from UNIX), slosh.

     circumflex, caret, uparrow, hat, chevron, sharkfin, to ("to
     the power of"), fang

     underscore, underline, underbar, under, score, backarrow

     grave accent, grave, backquote, left quote, open quote,
     backprime, unapostrophe, backspark, birk, blugle, back tick,

     open/close brace, left/right brace, brace/unbrace, curly
     bracket, curly/uncurly, leftit/rytit, embrace/bracelet

     vertical bar, bar, or, or-bar, v-bar, pipe, gozinta, thru,
     pipesinta (last four from UNIX)

     tilde, squiggle, approx, wiggle, twiddle, swung dash, enyay

   Some other common usages cause odd overlaps.  The ``$'', ``#'', and ``&''
   chars, for example, are all pronunced `hex' in different
   communities because various assemblers use them as a prefix tag for
   hexadecimal constants (in particular, $ in the 6502 world and & on
   the Sinclair and some other Z80 machines).

<asymptotic> adj. Infinitely close to.  This is used in a
   generalization of its mathematical meaning to allege that something
   is <within epsilon of> some standard, reference or goal (see

<autobogotiphobia> /aw'to-boh-got'@-foh`bee-uh/ n. See <bogotify>.

<automagically> /aw-toh-maj'i-klee/ or /aw-toh-maj'i-k@l-ee/ adv.
   Automatically, but in a way which, for some reason (typically
   because it is too complicated, or too ugly, or perhaps even too
   trivial), the speaker doesn't feel like explaining to you.  See
   <magic>.  "The C-INTERCAL compiler generates C, then automagically
   invokes `cc(1)' to produce an executable."

<awk> n. 1. [UNIX] An interpreted language developed by Aho, Weinberg
   and Kernighan, characterized by: C-like syntax, a BASIC-like
   approach to variable typing and declarations, associative arrays,
   and field-oriented text processing.  See also <PERL>. 2. Editing
   term for an expression awkward to manipulate through normal regular
   expression facilities.

                                {= B =}

<backbone cabal> n. A group of large-site administrators who pushed
   through the <Great Renaming> and reined in the chaos of <USENET>
   during most of the 1980s.  The cabal mailing list disbanded in late
   1988 after a bitter internal catfight, but the net hardly noticed.

<back door> n. A hole in the security of a system deliberately left in
   place by designers or maintainers.  The motivation for this is not
   always sinister; some operating systems, for example, come out of
   the box with privileged accounts intended for use by field service
   or the vendor's maintenance programmers.  Historically, back doors
   have often lurked in systems longer than anyone expected or
   planned, and a few have become widely known.  The famous RTM worm
   of late 1988, for example, used a back door in the BSD UNIX
   `sendmail(1)' utility.  Syn. <trap door>; may also be called a
   "wormhole".  See also <iron box>, <cracker>, <worm>, <logic

<background> vt.,adj. A task running in background is detached from
   the terminal where it was started (and often running at a lower
   priority); oppose <foreground>.  Nowadays this term is primarily
   associated with <UNIX>, but it was appears first to have been used
   in this sense on OS/360.  By extension, to do a task "in
   background" is to do it whenever <foreground> matters are not
   claiming your undivided attention, and "to background" something
   means to relegate it to a lower priority.  Compare <amp off>,

<Bad Thing> [from the 1926 Sellers & Yeatman parody `1066 and All
   That'] n. Something which can't possibly result in improvement of
   the subject.  This term is always capitalized, as in "Replacing
   all of the 9600 baud modems with bicycle couriers would be a Bad
   Thing."  Oppose <Good Thing>.  British correspondents confirm that
   <Bad Thing> and <Good Thing> (and prob. therefore <Right Thing> and
   <Wrong Thing>) come from the book referenced in the etymology,
   which discusses rulers who were Good Kings, but Bad Things.  This
   has apparently acreated mainstream idiom on their side of the pond.

<bagbiter> /bag'biet-@r/ n.  1. Something, such as a program or a
   computer, that fails to work, or works in a remarkably clumsy
   manner.  Example: "This text editor won't let me make a file with
   a line longer than 80 characters!  What a bagbiter!"  2.  A person
   who has caused you some trouble, inadvertently or otherwise,
   typically by failing to program the computer properly.  Synonyms:
   <loser>, <cretin>, <chomper>. 3. Also in the form <bagbiting> adj.
   Having the quality of a bagbiter.  `This bagbiting system won't let
   me compute the factorial of a negative number.'  Compare <losing>,
   <cretinous>, <bletcherous>, <barfucious> (under <barf>) and
   <chomping> (under <chomp>). 4. <bite the bag> vi.  To fail in some
   manner. "The computer keeps crashing every five minutes."  "Yes,
   the disk controller is really biting the bag."  The original
   loading of these terms was almost undoubtedly obscene, probably
   referring to the scrotum, but in their current usage they have
   become almost completely sanitized.

<bamf> /bamf/ [from old X-men comics] interj. Notional sound made by a
   person or object teleporting in or out of the hearer's vicinity.
   Often used in <virtual reality> (esp. <MUD>) electronic fora when a
   character wishes to make a dramatic entrance or exit.

<bandwidth> n. 1. Used by hackers in a generalization of its technical
   meaning as the volume of information per unit time that a computer,
   person or transmission medium can handle. "Those are amazing
   graphics but I missed some of the detail --- not enough bandwidth,
   I guess."  2. Attention span. 3. Very loosely, total data volume.
   "Never underestimate the bandwidth of a station-wagon full of
   magtapes."  4. On <USENET>, a measure of network capacity that is
   often wasted by people complaining about how network news items
   posted by others are a waste of bandwidth.

<bang> 1. n. Common spoken name for `!' (ASCII 33), especially when
   used in pronouncing a <bang path> in spoken hackish.  In elder days
   this was considered a CMUish usage, with MIT and Stanford hackers
   preferring <excl> or <shriek>; but the spread of UNIX has carried
   <bang> with it (esp. via the term <bang path>) and it is now
   certainly the most common spoken name for `!'.  Note that it is
   used exclusively for non-emphatic written `!'; one would not say
   "Congratulations bang.", but if one wanted to specify the exact
   characters "FOO!", one would speak "Eff oh oh bang".  See
   <shriek>, <ASCII>.  2.  interj. An exclamation signifying roughly
   "I have achieved enlightenment!" or "The dynamite has cleared
   out my brain!".  Often used to acknowledge that one has
   perpetrated a <thinko> immediately after one has been called on it

<bang path> n. An old-style UUCP electronic-mail address specifying
   hops to get from some assumed-reachable location to the addressee,
   so called because each hop is signified by a <bang> sign.  Thus the
   path "...!bigsite!foovax!barbox!me" directs correspondents to
   route their mail to machine bigsite (presumably a well-known
   location accessible to everybody) and from there through the
   machine "foovax" to the account of user "me" on "barbox".
   See <Internet address>, <network, the>, and <sitename>.

<bar> /bar/ 1. The second metasyntactic variable, after <foo> and
   before <baz>.  "Suppose we have two functions FOO and BAR.  FOO
   calls BAR..."  2. Often appended to <foo> to produce <foobar>.

<bare metal> n. 1. New computer hardware, unadorned with such snares
   and delusions as an <operating system>, <HLL> or even assembler.
   Commonly in the phrase "programming on the bare metal" which
   refers to the arduous work of <bit-bashing> needed to create these
   basic tools for a new machine.  Real bare-metal programming
   involves things like building boot proms and BIOS chips,
   implementing basic monitors used to test device drivers, and
   writing the assemblers that will be used to write the compiler back
   ends that will give the new machine a real development environment.
   2. The same phrase is also used to describe a style of
   <hand-hacking> that relies on bit-level peculiarities of a
   particular hardware design, esp. tricks for speed and space
   optimization that rely on crocks like overlapping opcodes (or, in
   one famous case, interleaving of opcodes on a magnetic drum to
   minimize fetch delays due to the device's rotational latency).
   This sort of thing has become less common as the relative costs of
   programming time and machine resources have changed, but is still
   found in heavily constrained environments like industrial embedded
   systems.  See <real programmer>.

<barf> /barf/ [from mainstream slang meaning "vomit"] 1. interj.
   Term of disgust.  See <bletch>.  2. To say "Barf!" or emit some
   similar expression of disgust. 3. vi. To fail to work because of
   unacceptable input.  May mean to give an error message.  Examples:
   "The division operation barfs if you try to divide by zero."
   (that is, division by zero fails in some unspecified spectacular
   way) "The text editor barfs if you try to read in a new file
   before writing out the old one."  4. Also <barfulous>,
   <barfucious>: adj.  Said of something which would make anyone barf,
   if only for aesthetic reasons.  See <choke>, <gag>.  Note that in
   Commonwealth English, "barf" is generally replaced by "puke" or
   "vom".  <barf> is sometimes also used as a metasyntactic variable
   like <foo> or <bar>.

<baroque> adj.  Feature-encrusted; complex; gaudy; verging on
   excessive.  Said of hardware or (esp.) software designs, this has
   many of the connotations of <elephantine> or <monstrosity> but is
   less extreme and not pejorative in itself.

<baud barf> /bawd barf/ n. The garbage one gets on the monitor when
   using a modem connection with some protocol setting (esp. line
   speed) incorrect, or when someone picks up a voice extension on the
   same line, or when really bad line noise disrupts the connection.
   Baud barf is not completely <random>, by the way; hackers with a
   lot of serial-line experience can usually tell whether the device
   at the other end is expecting a higher or lower speed than the
   terminal is set to.  *Really* experienced ones can identify
   particular speeds.

<baz> /baz/ 1. The third metasyntactic variable, after <foo> and <bar>
   and before <qux>.  "Suppose we have three functions FOO, BAR, and
   BAZ.  FOO calls BAR, which calls BAZ..." 2. interj. Term of mild
   annoyance.  In this usage the term is often drawn out for two or
   three seconds, producing an effect not unlike the bleating of a
   sheep; /baaaaaaz/.  3. Occasionally appended to <foo> to produce

<beam> [from Star Trek Classic's "Beam me up, Scotty!"] vt. To
   transfer <softcopy> of a file electronically; most often in
   combining forms such as "beam me a copy" or "beam that over to
   his site".  Compare <blast>, <snarf>, <BLT>.

<beep> n.,v. Syn. <feep>.  This term seems to be preferred among micro

<bells and whistles> [by analogy with steam calliopes] n. Features
   added to a program or system to make it more <flavorful> from a
   hacker's point of view, without necessarily adding to its utility
   for its primary function.  Distinguished from <chrome> which is
   intended to attract users.  "Now that we've got the basic program
   working, let's go back and add some bells and whistles."  However,
   no one seems to know what distinguishes a bell from a whistle.

<benchmark> n. An inaccurate measure of computer performance.  "In
   the computer industry, there are three kinds of lies: lies, damn
   lies, and benchmarks."  Well known ones include Dhrystone,
   Whetstone, Rhealstone (see <h infix>) and LINPACK. See also
   <machoflops>, <MIPS>.

<berklix> /ber'kliks/ n.,adj. Contraction of Berkeley UNIX.  See
   <BSD>.  Not used at Berkeley itself.  May be more common among
   <suits> attempting to sound like cognoscenti than hackers, who
   usually just say `BSD'.

<Berzerkely> [from "berserk"] /b@r-zer'klee/ [from the name of a
   now-deceased record label] n. Humorous, distortion of "Berkeley"
   used esp.  to refer to the practices or products of the <BSD> UNIX
   hackers.  See <software bloat>, <Missed'em-five>.

<beta> /bay'-ta/ n. 1. In the <Real World> software often goes through
   two stages of testing: Alpha (in-house) and Beta (out-house?).
   Software is said to be "in beta".  2. Beta software is
   notoriously buggy, hence anything that is new and experimental is
   "in beta". As in, "His girlfriend is in beta".

<BFI> n. See <brute force and ignorance>.

<bible> n. As used by hackers, usually refers to one of a small number
   of fundamental source books including <Knuth> or <K&R>.

<biff> /bif/ [USENET] n.  The most famous <pseudo>, and the
   prototypical <newbie>.  Articles from BIFF are characterized by all
   upper case letters sprinkled liberally with bangs, typos, "cute"
   long <sig block> (sometimes even a <doubled sig>), and unbounded
   naivete.  BIFF posts articles using his elder brother's VIC-20.
   BIFF's location is a mystery, as his articles appear to come from a
   variety of sites.  However, BITNET seems to be the most frequent
   origin.  The theory that BIFF is a denizen of BITNET is supported
   by BIFF's (unfortunately invalid) electronic mail address:
   BIFF@BIT.NET. See also <doubled sig>.

<biff> v. To notify someone of incoming mail; from the BSD utility
   `biff(1)' which was in turn named after the implementor's dog.

<big-endian> [From Swift's `Gulliver's Travels' via a famous 1980
   paper `On Holy Wars and a Plea for Peace' by Danny Cohen] adj.
   Describes a computer architecture in which, within a given 16- or
   32-bit word, lower byte addresses have higher significance (the
   word is stored `big-end-first').  Most processors including the IBM
   370 family and the <PDP-10> and Motorola microprocessor families
   and most of the various RISC designs current in 1990 are
   big-endian.  See <little-endian>, <middle-endian>, <NUXI problem>.

<Big Grey Wall> n. What greets a <VMS> user searching for
   documentation.  A full VMS kit comes on a pallet, the documentation
   taking up around 15 feet of shelf space before adding layered
   products such as compilers, databases, multivendor networking,
   programming tools etc. Recent (since VMS V5) DEC documentation
   comes with grey binders; under VMS V4 the binders were orange
   ("big orange wall"), under V3 they were blue.  See <VMS>.

<big iron> n. Large, expensive, ultra-fast computers.  Used generally
   of number crunching supercomputers such as Crays, but can include
   more conventional big commercial IBMish mainframes.  Term of
   approval; compare <heavy metal>, oppose <dinosaur>.

<big red switch> [IBM] n. The power switch on a computer, esp. on an
   IBM-PC where it really is large and red.  "This !@%$% <bitty box>
   is hung again, time to hit the big red switch."  Sources at IBM
   report that, in tune with the company's passion for <TLA>s
   this is often acronymized as "BRS".

<bignum> /big'num/ [orig. from MIT MACLISP; the name is said to derive
   from a pun on the FORTRAN REAL type] n.  1. A multiple-precision
   computer representation for very large integers.  More generally,
   any very large number.  "Have you ever looked at the United States
   Budget?  There's bignums for you!"

   Most computer languages provide a kind of data called "integer",
   but such computer integers are usually very limited in size;
   usually they must be smaller than 2 ^ 31 (2147483648) or (on a
   losing <bitty box>) 2 ^ 15 (32767).  If you want to work with
   numbers larger than that, you have to use floating-point numbers,
   which are usually only accurate to six or seven decimal places.
   Computer languages that provide bignums can perform exact
   calculations on very large numbers, such as 1000! (the factorial of
   1000, which is 1000 times 999 times 998 times ... times 2 times 1)
   exactly.  For example, this value for 1000! was computed by the
   MACLISP system using bignums:


   2. BIGNUMS [from Macsyma] n. In backgammon, large numbers on the
   dice, especially a roll of double fives or double sixes.  See also
   <El Camino Bignum>.

<bit> [from the unit of information] n.  1. The unit of information;
   the amount of information obtained by asking a yes-or-no question
   (this is straight technicalese).  2. A computational quantity that
   can take on one of two values, such as true and false, or zero and
   one.  3. A mental flag: a reminder that something should be done
   eventually.  Example: "I have a bit set for you." (I haven't seen
   you for a while, and I'm supposed to tell or ask you something.)  A
   bit is said to be "set" if its value is true or one, and
   "reset" or "clear" if its value is false or zero.  One speaks
   of setting and clearing bits.  To "toggle" or "invert" a bit is
   to change it, either from zero to one or from one to zero.

<bit bang> n. Transmission of data on a serial line accomplished by
   rapidly tweaking a single output bit at the appropriate times
   (popular on certain early models of Prime computers, presumably
   when UARTs were too expensive; and on archaic Z-80 micros with a
   Zilog PIO but no SIO).  The technique is a simple loop with eight
   OUT, SHIFT, OUT etc. instructions for each byte.  Input is more
   interesting.  And full duplex (doing input and output at the same
   time) is one way to separate the real hackers from the wannabees.

<bit bashing> n. (also, "bit diddling" or "bit twiddling") Term
   used to describe any of several kinds of low-level programming
   characterized by manipulation of <bit>, <flag>, <nybble> and other
   smaller-than-character sized pieces of data: these include
   low-level device control, encryption algorithms, checksum and
   error-correcting codes, hash functions, some flavors of graphics
   programming (see <bitblt>), and assembler/compiler code generation.
   May connote either tedium or a real technical challenge (more
   usually the former)."The command decoding for the new tape driver
   looks pretty solid but the bit-bashing for the control registers
   still has bugs."  See also <bit bang>.

<bit bucket> n. The great data sink in the sky (originally, the
   mythical receptacle used to catch bits when they fall off the end
   of a register during a shift instruction).  Data that is discarded,
   lost, or destroyed is said to "go to the bit bucket".  On <UNIX>,
   often used for </dev/null>.  Sometimes amplified as "the Great Bit
   Bucket in the Sky".  This term is used purely in jest.  It's based
   on the fanciful notion that bits are objects that are not
   destroyed, but only misplaced.  See also <null device>.

<bit decay> n. See <software rot>.  People with a physics background
   tend to prefer this one for the analogy with particle decay.

<bit rot> n. See <software rot>.

<bitblt> /bit'blit/ or /bit'belt/ n. [from <BLT>, q.v.] 1. Any of a
   closely related family of algorithms for moving and copying
   rectangles of bits between main and display memory on a bit-mapped
   device, or between two areas of either main or display memory (the
   requirement to do the Right Thing in the case of overlapping source
   and destination rectangles is what makes BitBlt tricky).  2.
   Synonym for <blit> or <BLT>

<bits> n.  1. Information.  Examples: "I need some bits about file
   formats."  ("I need to know about file formats.")  Compare <core
   dump>, sense #4. 2.  Machine-readable representation of a document,
   specifically as contrasted with paper.  "I only have a photocopy
   of the Jargon File; does anyone know where I can get the bits?".
   See <softcopy>.  3. Also in <the source of all good bits> n.  A
   person from whom (or a place from which) information may be
   obtained.  If you need to know about a program, a <wizard> might be
   the source of all good bits.  The title is often applied to a
   particularly competent secretary.

<bitty box> /bit'ee boks/ n. 1. A computer sufficiently small,
   primitive or incapable as to cause a hacker acute claustrophobia at
   the thought of developing for it.  Especially used of small,
   obsolescent, single-tasking-only personal machines like the Atari
   800, Osborne, Sinclair, VIC-20, or TRS-80. 2. More generally, the
   opposite of `real computer' (see <Get a real computer!>).
   Pejorative.  See also <mess-dos>, <toaster>, and <toy>.

<bixie> /biks'ee/ n. Synonym for <emoticon> used on BIX (the Byte
   Information Exchange); BIXers believe (probably incorrectly) the
   emoticon was invented there.

<black art> n. A collection of arcane, unpublished, and (by
   implication) mostly ad-hoc techniques developed for a particular
   application or systems area.  VLSI design and compiler code
   optimization were (in their beginnings) considered classic examples
   of black art; as theory developed they became <deep magic>, and
   once standard textbooks had been written became merely <heavy
   wizardry>.  The huge proliferation of formal and informal channels
   for spreading around new computer-related technologies during the
   last twenty years has made both the term "black art" and what it
   describes less common than formerly.  See also <voodoo

<black hole> n. When a piece of email or netnews disappears
   mysteriously between its origin and destination sites (that is,
   without returning a <bounce message>) it is commonly said to have
   "fallen into a black hole".  Similarly, one might say "I think
   there's a black hole at foovax!" to convey suspicion that site
   foovax has been dropping a lot of stuff on the floor lately (see
   <drop on the floor>).  The implied metaphor of email as
   interstellar travel is interesting in itself.

<blast> vt.,n. Synonym for <BLT>, used esp. for large data sends over
   a network or comm line.  Opposite of <snarf>.  Usage: uncommon.
   The variant `blat' has been reported.  2. v. [HP/Apollo] Synonymous
   with <nuke> (sense #3).  Sometimes the message "Unable to kill all
   processes.  Blast them (y/n)?" would appear in the command window
   upon logout.

<blazer> n. Nickname for the Telebit Trailblazer, an expensive but
   extremely reliable and effective high-speed modem, popular at UNIX
   sites that pass large volumes of <email> and <USENET> news.

<bletch> /blech/ [from Yiddish/German "brechen", to vomit] 1.
   interj.  Term of disgust.

<bletcherous> /blech'@-rus/ adj. Disgusting in design or function;
   aesthetically unappealing.  This word is seldom used of people.
   "This keyboard is bletcherous!" (Perhaps the keys don't work very
   well, or are misplaced).  See <losing>, <cretinous>, <bagbiter>,
   <bogus>, and <random>.  <bletcherous> applies to the aesthetics of
   the thing so described; similarly for <cretinous>.  By contrast,
   something that is <losing> or <cretinous> may be failing to meet
   objective criteria.  See <bogus> and <random>, which have richer
   and wider shades of meaning than any of the above.

<blinkenlights> /blink'@n-lietz/ n. Front-panel diagnostic lights on
   a mainframe CPU.  Derives from the last word of the famous
   blackletter-Gothic "ACHTUNG! ALLES LOOKENSPEEPERS!" notice in
   mangled pseudo-German that once graced about half the computer
   rooms in the English-speaking world.  The sign in its entiretu ran:

                        ACHTUNG! ALLES LOOKENSPEEPERS
     Das computermachine ist nicht fur gefingerpoken und mittengrabben.
     Ist easy schnappen der springenwerk, blowenfusen und poppencorken
     mit spitzensparken.  Ist nicht fur gewerken bei das dumpkopfen.
     Das rubbernecken sichtseeren keepen hans in das pockets muss;
     relaxen und watch das blinkenlichten.

   This silliness dates back at least as far as 1959 at Stanford
   University and had already gone international by the early '60s,
   when it was reported at London University's ATLAS computing site.
   There are several variants of it in circulation, some of which
   actually do end with the word `blinkenlights';.  It is reported, by
   the way, that an analogous travesty in mangled English is posted in
   German computer laboratories.

<blit> /blit/ vt.  1. To copy a large array of bits from one part of a
   computer's memory to another part, particularly when the memory is
   being used to determine what is shown on a display screen.  "The
   storage allocator picks through the table and copies the good parts
   up into high memory, and at the end BLITs it all back down again."
   See <bitblt>, <BLT>, <DD>, <cat>, <blast>, <snarf>.  More
   generally, to perform some operation (such as toggling) on a large
   array of bits while moving them.  2. An early experimental
   bit-mapped terminal designed by Rob Pike at Bell Labs, later
   commercialized as the AT&T 5620.

<block> [From computer science usage] 1. vi. To delay while waiting
   for something.  "We're blocking until everyone gets here."  2. in
   <block on> vt. To block, waiting for (something).  "Lunch is
   blocked on Phil's arrival."

<block transfer computations> n. From the Dr. Who television series:
   in the show, it referred to computations so fiendishly subtle and
   complex that they could not be performed by machines.  Used to
   refer to any task that should be expressible as an algorithm in
   theory, but isn't.

<blow away> vt. To remove files and directories from permanent storage
   with extreme prejudice, generally by accident.  Oppose <nuke>.

<blow out> vi. Of software, to fail spectacularly; almost as serious
   as <crash and burn>.  See <blow past>.

<blow past> vi. To <blow out> despite a safeguard.  "The server blew
   past the 5K reserve buffer."

<blow up> vi. [scientific computation] To become unstable.  Suggests
   that the computation is diverging so rapidly that it will soon
   either overflow or at least go <nonlinear>.

<blt> /bee ell tee/ or (rarely) /belt/ n.,v. 1. Synonym for <blit>.
   This is the original form of <blit> and the ancestor of <bitblt>.
   In these versions the usage has outlasted the <PDP-10> BLock
   Transfer instruction for which <BLT> derives; nowadays, the
   assembler mnemonic <BLT> almost always means `Branch if Less Than

<Blue Book> n. 1. Informal name for one of the three standard
   references on the page-layout and graphics-control language
   PostScript (`PostScript Language Tutorial and Cookbook', Adobe
   Systems, Addison-Wesley 1985, QA76.73.P67P68, ISBN 0-201-10179-3);
   the other two official guides are known as the <Green Book> and
   <Red Book>.  2. `Smalltalk-80: The Language and its
   Implementation'. David Robson, Addison-Wesley 1983, QA76.8.S635G64,
   ISBN 0-201-11371-63 (this is also associated with green and red
   books).  3. Any of the 1988 standards issues by the CCIT 9th
   plenary assembly.  Until now, they have changed color each review
   cycle (1984 was <Red Book>, 1992 would be <Green Book>); however,
   it is rumored that this convention is going to be dropped befor
   1992.  These include, among other things, the X.400 email spec and
   the Group 1 through 4 fax standards.  See also <Red Book>, <Green
   Book>, <Silver Book>, <Purple Book>, <Orange Book>, <White Book>,
   <Pink-Shirt Book>, <Dragon Book>, <Aluminum Book>.

<Blue Glue> [IBM] n. IBM's SNA (Systems Network Architecture) an
   incredibly losing and bletcherous protocol suite widely favored at
   commercial shops that don't know any better.  See <fear and
   loathing>.  It may not be irrelevant that <Blue Glue> is the trade
   name of a 3M product that is commonly used to hold down the carpet
   squares to the removable panel floors so common in computer
   installations.  A correspondent at U.Minn. reports that the CS dept
   there has about 80 bottles of Blue Glue hanging about, so they
   often refer to any messy work to be done `using the blue glue".

<blue goo> n. Term for "police" <nanobot>s intended to prevent <gray
   goo>, denature hazardous waste, destroy pollution, put ozone back
   into the stratosphere, prevent halitosis, and to promote truth,
   justice, and the American way, etc., etc.  See <nanotechnology>.

<BNF> /bee-en-ef/ n. 1. Acronym for `Backus-Naur Form', a
   metasyntactic notation used to specify the syntax of programming
   languages, command sets and the like.  Widely used for language
   descriptions but seldom documented anywhere, so that it must
   usually be learned by osmosis from other hackers.  Consider this
   BNF for a postal address:

      <postal-address> ::= <name-part> <street-address> <zip-part>

      <name-part> ::= <first-name> [<middle-part>] <last-name>

      <middle-part> ::= <middle-name> | <middle-initial> "."

      <street-address> ::= [<apt>] <street-number> <street-name>

      <zip-part> ::= <town-name> "," <state-code> <zip-code>

   This translates into English as: A postal-address consists of a
   name-part, followed by a street-address part, followed by a
   zip-code part.  A name-part consists of a first-name followed by an
   optional middle-part followed by a last-name.  A middle-part
   consists of either a middle name or a middle initial followed by a
   dot.  A street address consists of an optional apartment specifier
   followed by a street number, followed by a street name.  A zip-part
   consts of a town-name, followed by a state code, followed by a zip
   code.  Note that many things such as the format of a first-name,
   apartment specifier or zip-code are left unspecified.  These are
   presumed to be obvious from context or detailed in another part of
   the specification the BNF is part of.  See also <PARSE>.

   A major reason BNF is listed here is that the term is also used
   loosely for any similar notation, possibly containing some or all
   of the <GLOB> wildcards.

   2. In <SCIENCE-FICTION FANDOM> BNF expands to `Big Name Fan'
   (someone famous or notorious).  Years ago a fan started handing out
   black-on-green BNF buttons at SF conventions.  This confused the
   hacker contingent terribly.

<boa> [IBM] n. Any one of the fat cables that lurk under the floor in
   a <dinosaur pen>.  It is rumored within IBM that 370 channel cables
   are limited to 200 feet because beyond that length the boas get

<boat anchor> n. Like <doorstop> but more severe, implies that the
   offending hardware is irreversibly dead or useless.

<bogometer> n. See <bogosity>.

<bogon> /boh'gon/ [by analogy with proton/electron/neutron, but
   doubtless reinforced after 1980 by the similarity to Douglas
   Adams's "Vogons", see Appendix C] n. 1. The elementary particle
   of bogosity (see <quantum bogodynamics>).  For instance, "the
   ethernet is emitting bogons again", meaning that it is broken or
   acting in an erratic or bogus fashion. 2. A query packet sent from
   a TCP/IP domain resolver to a root server, having the reply bit set
   instead of the query bit.  3.  Any bogus or incorrectly formed
   packet sent on a network.  4. By extension, used to refer
   metasyntactically to any bogus thing, as in "I'd like to go to
   lunch with you but I've got to go to the weekly staff bogon." 5. A
   person who is bogus or who says bogus things.  This was
   historically the original usage, but has been overtaken by its
   derivatives in 1-4.

<bogon filter> /boh'gon fil'tr/ n.  Any device, software or hardware,
   which limits or suppresses the flow and/or emission of bogons.
   Example: "Engineering hacked a bogon filter between the Cray and
   the VAXen and now we're getting fewer dropped packets."

<bogosity> /boh-go's@-tee/ n. 1. The degree to which something is
   <bogus>.  At CMU, bogosity is measured with a <bogometer>; typical
   use: in a seminar, when a speaker says something bogus, a listener
   might raise his hand and say, "My bogometer just triggered". 2.
   The potential field generated by a bogon flux; see <quantum

<bogotify> /boh-go't@-fie/ vt. To make or become bogus.  A program
   that has been changed so many times as to become completely
   disorganized has become bogotified.  If you tighten a nut too hard
   and strip the threads on the bolt, the bolt has become bogotified
   and you'd better not use it any more.  This coinage led to the
   notional <autobogotiphobia> (aw'to-boh-got'@-foh`bee-uh) n.,
   defined as the fear of becoming bogotified; but is not clear that
   the latter has ever been `live' slang rather than a self-conscious
   joke in jargon about jargon.

<bogue out> /bohg owt/ vi. to becomes bogus, suddenly and
   unexpectedly.  "His talk was relatively sane until somebody asked
   him a trick question, then he bogued out and did nothing but
   <flame> afterwards."

<bogus> [WPI, Yale, Stanford] adj. 1. Non-functional.  "Your patches
   are bogus."  2. Useless.  "OPCON is a bogus program."  3.
   False.  "Your arguments are bogus."  4. Incorrect.  "That
   algorithm is bogus."  5. Unbelievable.  "You claim to have solved
   the halting problem for Turing Machines?  That's totally bogus."
   6. Silly.  "Stop writing those bogus sagas."  Astrology is bogus.
   So is a bolt that is obviously about to break.  So is someone who
   makes blatantly false claims to have solved a scientific problem.
   (This word seems to have some, but not all, of the connotations of

   [Etymological note: "Bogus" was originally used in the hackish
   sense at Princeton, in the late 60s.  It was used not particularly
   in the CS department, but all over campus.  It came to Yale, where
   one of us (Lehman) was an undergraduate, and (we assume) elsewhere
   through the efforts of Princeton alumni who brought the word with
   them from their alma mater.  In the Yale case, the alumnus is
   Michael Shamos, who was a graduate student at Yale and is now a
   faculty member here.  A glossary of bogus words was compiled at
   Yale when the word was first popularized (see <autobogotiphobia>
   under <bogotify>).  By the mid-1980s it was also current in
   something like the hackish sense in West Coast teen slang]

   Further note: A correspondent at Cambridge claims these uses of
   bogus grate on British nerves; in Britain the word means rather
   specifically `counterfeit' as in "a bogus pound note".

<Bohr bug> /bohr buhg/ [from quantum physics] n. A repeatable <bug>;
   one which manifests reliably under a possibly unknown but
   well-defined set of conditions.  Antonym of <heisenbug>.

<boink> /boynk/ [USENET] 1. To have sex with; compare <bounce>, sense
   #3.  In Commonwealth English this the variant "bonk" is more
   common.  2. After the original Peter Korn "Boinkon" <USENET>
   parties, used for almost any net social gathering, e.g.  Miniboink,
   a small boink held by Nancy Gillett in 1988; Minniboink, a Boinkcon
   in Minnesota in 1989; Humpdayboinks, Wednesday get-togethers held
   in the San Francisco Bay Area.  Compare <@-party>.

<bomb> vi. 1. General synonym for <crash>, esp. used of software or OS
   failures. "Don't run Empire with less than 32K stack, it'll bomb
   out" 2. Atari ST and Macintosh equivalents of <panic> or <guru>
   (sense 2), where icons of little black-powder bombs or mushroom
   clouds are displayed indicating the system has died.  On the Mac
   this may be accompanied by a hexadecimal number indicating what
   went wrong, similar to the Amiga GURU MEDITION number.  <Mess-dos>
   machines tend to get <locked up> in this situation.

<bondage-and-discipline language> A language such as Pascal, APL, or
   Prolog that, though ostensibly general-purpose, is designed so as
   to enforce an author's theory of "right programming" even though
   said theory is demonstrably inadequate for systems or even vanilla
   general-purpose programming.  Often abbreviated "B&D"; thus, one
   may speak of things "having the B&D nature" etc.  See <Languages
   of Choice>.

<bonk/oif> interj. On some <MUD> versions, a `:bonk' command allows
   one to express pique or censure; you give it a target name, and the
   message everyone sees is of the form `Foo bonks bar'.  There is a
   convention that one should acknowledge a bonk by saying `oif!' and
   a myth to the effect that failing to do so upsets the cosmic
   bonk/oif balance, causing much trouble in the universe.  See also
   <talk mode>.

<boot> [from "by one's bootstraps"] vi.,n. To load and initialize
   the operating system on a machine.  This usage is no longer slang
   (having become jargon in the strict sense), but it is sometimes
   used of human thought processes, as in the following exchange:
   "You've lost me." "O.K., reboot.  Here's the theory...".  Also
   found in the variants "cold boot" (from power-off condition) and
   "warm boot" (with the CPU and all devices already powered up, as
   after a hardware reset or software crash).

<bottleneck> adj. 1. Used by hackers specifically to describe hardware
   under which performance is usually limited by contention for one
   particular resource (such as disk, memory or processor <clocks>);
   the opposite condition is called `balanced', which is more jargon
   in the strict sense and may be found in technical dictionaries. 2.
   Less often, applied to the software analogue of sense #1, a slow
   code section or algorithm through which all computation must pass
   (see also <hot spot>).

<bounce> v. 1. [UNIX, perhaps from "to bounce a check"] An
   electronic mail message which is undeliverable and returns an error
   notification to the sender is said to `bounce'.  See also <bounce
   message>. 2. [Stanford] To play volleyball.  At one time there was
   a volleyball court next to the computer laboratory.  From 5:00 PM
   to 7:00 PM was the scheduled maintenance time for the computer, so
   every afternoon at 5:00 the computer would become unavailable, and
   over the intercom a voice would cry , "Bounce, bounce!"  3. To
   engage in sexual intercourse; prob.  fr.  the expression "bouncing
   the mattress", but influenced by Piglet's psychosexually-loaded
   "Bounce on me too, Tigger!" from the Winnie the Pooh books.  4.
   To casually reboot a system in order to clear up a transient
   problem.  Reported primarily among <VMS> users.

<bounce message> [UNIX] n. Notification message returned to sender by
   a site unable to relay <email> to the intended <Internet address>
   recipient or the next link in a <bang path> (see <bounce>).
   Reasons might include a nonexistent or misspelled username or a
   down relay site.  Bounce messages can themselves fail, with
   occasionally ugly results; see <sorcerer's apprentice mode>.

<box> [within IBM] n. Without qualification but within an SNA-using
   site, this refers specifically to an IBM front-end processor or
   FEP.  An FEP is a small computer necessary to enable an IBM
   mainframe to communicate beyond the limits of the <dinosaur pen>.
   Typically used in expressions like the cry that goes up when an SNA
   network goes down, "Looks like the <box> has <fallen over>."  See
   also <IBM>, <fear and loathing>, <Blue Glue>.

<boxen> /bok'sn/ pl n. [by analogy with <VAXen>] Fanciful plural of
   `box' often encountered in the phrase `UNIX boxen', used to
   describe commodity <UNIX> hardware.  The implication is that any
   two UNIX boxen are interchangeable.

<brain-damaged> [generalization of "Honeywell Brain Damage" (HBD), a
   theoretical disease invented to explain certain utter cretinisms in
   Honeywell <Multics>] adj.  Obviously wrong; <cretinous>;
   <demented>.  There is an implication that the person responsible
   must have suffered brain damage, because he should have known
   better.  Calling something brain-damaged is really bad; it also
   implies it is unusable, and that its failure to work is due to poor
   design rather than some accident.

<brain-dead> adj. Brain-damaged in the extreme.  Not quite like
   mainstream use, as it tends to imply terminal design failure rather
   than malfunction or simple stupidity.

<brain dump> [Sun] n. Comprehensive exchange of knowledge between
   people.  "Let's get together for a brain dump before you take
   off."  At Sun, this is also known as `TOI' (transfer of

<braino> /bray'no/ n. Syn. for <thinko>.

<branch to Fishkill> [IBM, from the location of one of their
   facilities] n. Any unexpected jump in a program that produces
   catastrophic or just plain weird results.  See <hyperspace>.

<break> v. 1. To cause to be broken (in any sense).  "Your latest
   patch to the editor broke the paragraph commands."  2. (of a
   program) To stop temporarily, so that it may be examined for
   debugging purposes.  The place where it stops is a "breakpoint".
   3. To send an RS-232 "break" (125 msec. of line high) over a
   serial comm line. 4. [UNIX] To strike whatever key currently causes
   the tty driver to send SIGINT to the current process.  Normally
   "break" (sense 3) or delete does this.

<breakage> [IBM] n. The extra people that must be added to an
   organization because its master plan has changed; used esp. of
   software and hardware development teams.

<brittle> adj. Said of software that's functional but easily broken by
   changes in operating environment or configuration.  Often describes
   the results of a research effort that were never intended to be
   robust, but can be applied to commercially developed software.
   Oppose <robust>.

<broadcast storm> n. An incorrect packet broadcast on a network that
   causes most hosts to respond all at once, typically with wrong
   answers that start the process over again.  Also called <network
   meltdown>.  See also <Chernobyl packet>.

<broken> adj. 1. Not working properly (of programs).  2.  Behaving
   strangely; especially (of people), exhibiting extreme depression.

<broket> /broh'k@t/ or /broh'ket/ [by analogy with "bracket": a
   "broken bracket"] n. Either of the characters "<" and ">".
   This word originated as a contraction of the phrase "broken
   bracket", that is, a bracket that is bent in the middle.  (At MIT,
   and apparently in <Real World> as well, these are usually called
   <angle brackets>.)

<brute force> adj. Describes a certain kind of primitive programming
   style; broadly speaking, one which ignores scaling problems and
   applies naive methods suited to small problems directly to large
   ones.  An example of a brute-force program is one that sorts a
   thousand numbers by examining them all, picking the smallest one,
   and saving it in another table; then examining all the numbers
   again, and picking the smallest one except for the one it already
   picked; and in general choosing the next number by examining all
   one thousand numbers and choosing the smallest one that hasn't yet
   been picked (as determined by examining all the ones already
   picked).  Yes, the program will produce the right answer, but it
   will be much slower than a program that uses even a modicum of
   cleverness to avoid most of the work.

<brute force and ignorance> n. A popular design technique at many
   software houses --- <brute force> coding unrelieved by any
   knowledge of how problems have been previously solved in elegant
   ways.  Dogmatic adherence to design methodologies tends to
   encourage it.  Characteristic of early <larval stage> programming;
   unfortunately, many never outgrow it.  Often abbreviated BFI, as
   in: "Gak, they used a bubble sort!  That's strictly from BFI."
   (this comment might be used by a hacker to describe the example
   given under <brute force> above).  Compare <bogosity>.

<BSD> /bee-ess-dee/ n. [acronym for Berkeley System Distribution] a
   family of <UNIX> versions for the DEC <VAX> developed by Bill Joy
   and others at University of California at Berkeley starting around
   1980, incorporating TCP/IP networking enhancements and many other
   features.  The BSD versions (4.1, 4.2, and 4.3) and commercial
   versions derived from them (SunOS and Mt. Xinu) held the technical
   lead in the UNIX world until AT&T's successful standardization
   efforts after about 1986, and are still widely popular.  See
   <UNIX>, <USG UNIX>.

<bucky bits> /buh'kee bits/ [primarily Stanford] n. The bits produced
   by the CTRL and META shift keys, esp. on a Stanford (or Knight)
   keyboard (see <space-cadet keyboard>).  It is rumored that these
   were in fact named for Buckminster Fuller during a period when he
   was consulting at Stanford.  Unfortunately, legend also has it that
   "Bucky" was Niklaus Wirth's nickname when *he* was
   consulting at Stanford and that he first suggested the idea of the
   meta key, so its bit was named after him.  See <double bucky>,
   <quadruple bucky>.

<buffer overflow> n. What typically happens when an <OS> or
   application is fed data faster than it can handle.  Used
   metaphorically of human mental processes. "Sorry, I got four phone
   calls in three minutes last night and lost your message to a buffer

<bug> n. An unwanted and unintended property of a program or hardware,
   esp. one which causes it to malfunction.  Antonym of <feature>.
   Examples: "There's a bug in the editor: it writes things out
   backwards."  "The system crashed because of a hardware bug."
   "Fred is a winner, but he has a few bugs."  (e.g. Fred is a good
   guy, but he has a few personality problems.)

   Some have said this term came from telephone company usage: "bugs
   in a telephone cable" were blamed for noisy lines, but this
   appears to be an incorrect `folk etymology'.  Admiral Grace Hopper
   (an early computing pioneer better known for inventing COBOL) liked
   to tell a story in which a technician solved a persistent glitch in
   the Harvard Mark II machine by pulling an actual physical bug out
   from between the contacts of one of its relays, and she
   subsequently promulgated <bug> in its hackish sense as a joke about
   the incident (though, as she was careful to admit, she was not
   there when it happened).  For many years the logbook associated
   with the incident and the actual bug in question (a moth) sat in a
   display case at the Naval Surface Warfare Center, and now resides
   in the Smithsonian.  The entire story, with a picture of the
   logbook and the moth taped into it, is recorded in the Annals of
   the History of Computing (Volume 3, Number 3 (July 1981) on pages
   285 and 286.

   Interestingly, the text of the log entry, which is said to read
   "First example of an actual computer `bug'." establishes that the
   term was already in use at the time; and a similar incident is
   alleged to have occurred on the original ENIAC machine.  Indeed,
   the use of "bug" to mean an industrial defect was already
   established in Thomas Edison's time, and "bug" in the sense of an
   annoyance goes back to Shakespeare!

   In any case, in hacker's slang the word almost never refers to
   insects.  Here is a plausible conversation that never actually

   "This ant-farm has a bug."

   "What do you mean?  There aren't even any ants in it."

   "That's the bug."

<bug compatible> n. Said of a design or revision the design of which
   has been badly compromised by a requirement to be compatible with
   <fossil>s or <misfeature>s in other programs or (esp.) previous
   releases of itself.

<bulletproof> adj. Used of an algorithm or implementation considered
   extremely <robust>; lossage-resistant; capable of correctly
   recovering from any imaginable exception condition.  This is a rare
   and valued quality.  Syn. "armor-plated".

<bum> 1. vt. To make highly efficient, either in time or space, often
   at the expense of clarity.  "I managed to bum three more
   instructions out of that code."  2. n. A small change to an
   algorithm, program, or hardware device to make it more efficient.
   "This hardware bum makes the jump instruction faster."  Usage:
   now uncommon, largely superseded by <tune>.  Note that both these
   uses are rare in Commonwealth English, where "bum" is interpreted
   as a rude synonym for "buttocks".

<bump> vt. Synonym for increment.  Has the same meaning as C's ++
   operator.  Used esp. of counter variables, pointers and index
   dummies in for, while, and do-until loops.

<burble> vi. Like <flame>, but connotes that the source is truly
   clueless and ineffectual (mere flamers can be competent).  A term
   of deep contempt.

<busy-wait> vi. To wait on an event by <spin>ning through a tight or
   timed-delay loop that polls for the event on each pass, as opposed
   to setting up an interrupt handler and continuing execution on
   another part of the task.  A wasteful technique, best avoided on
   time-sharing systems where a busy-waiting program may hog the
   processor.  Syn. <spin-lock>

<buzz> vi. 1. Of a program, to run with no indication of progress and
   perhaps without guarantee of ever finishing; esp. said of programs
   thought to be executing tight loops of code.  The state of a
   buzzing program resembles <catatonia>, but you never get out of
   catatonia, while a buzzing loop may eventually end of its own
   accord.  Example: "The program buzzes for about ten seconds trying
   to sort all the names into order."  See <spin>.  2. [ETA Systems]
   To test a wire or PCB trace for continuity by applying an AC signal
   as opposed to applying a DC signal.  Some wire faults will pass DC
   tests but fail a buzz test.

<BWQ> /bee duhb'l-yoo kyoo/ [IBM] n. Buzz Word Quotient.  Usually
   roughly proportional to <bogosity>.  See <TLA>.

<bytesexual> /biet-seks'u-@l/ adj. Said of hardware, denotes
   willingness to compute or pass data in either <big-endian> or
   <little-endian> format (depending, presumably, on a mode bit
   somewhere).  See also <NUXI problem>

                                {= C =}

<C> n. 1. The third letter of the Latin alphabet. 2. The name of a
   programming language designed by Dennis Ritchie during the early
   1970s and first used to implement <UNIX>.  So called because many
   features derived from an earlier interpreter named `B' in
   commemoration of *its* parent, BCPL; before Bjarne Stroustrup
   settled the question by designing C++, there was a humorous debate
   over whether C's successor should be named `D' or `P'.  C became
   immensely popular outside Bell Labs after about 1980 and is now the
   dominant language in systems and microcomputer applications
   programming.  See <languages of choice>.

<can> vt. To abort a job on a time-sharing system.  Used esp. when the
   person doing the deed is an operator, as in "canned from the
   console".  Frequently used in an imperative sense, as in "Can
   that print job, the LPT just popped a sprocket!".  Synonymous with
   <gun>.  It is said that the ASCII character with mnemonic CAN
   (0011000) was used as a kill-job character on some early OSs.

<calculator> [Cambridge] n. Syn. for <bitty box>.

<canonical> adj. The usual or standard state or manner of something.
   This word has a somewhat more technical meaning in mathematics.
   For example, one sometimes speaks of a formula as being in
   canonical form.  Two formulas such as "9 + x" and "x + 9" are
   said to be equivalent because they mean the same thing, but the
   second one is in canonical form because it is written in the usual
   way, with the highest power of x first.  Usually there are fixed
   rules you can use to decide whether something is in canonical form.
   The slang meaning is a relaxation of the technical meaning (this
   generalization is actually not confined to hackers, and may be
   found throughout academia).

   A true story: One Bob Sjoberg, new at the MIT AI Lab, expressed
   some annoyance at the use of jargon.  Over his loud objections, we
   made a point of using jargon as much as possible in his presence,
   and eventually it began to sink in.  Finally, in one conversation,
   he used the word "canonical" in jargon-like fashion without
   thinking.  Steele: "Aha!  We've finally got you talking jargon
   too!"  Stallman: "What did he say?"  Steele: "Bob just used
   `canonical' in the canonical way."

<card walloper> n. An EDP programmer who works on batch programs that
   do stupid things like print people's paychecks.  Compare <code

<casters-up mode> /cas'trz uhp mohd/ [IBM] n. Yet another synonym for
   `broken' or `down'.

<casting the runes> n. The act of getting a <guru> to run a particular
   program and type at it because it never works for anyone else; esp.
   used when nobody can ever see what the guru is doing different from
   J. Random Luser does.  Compare <incantation>, <runes>, <examining
   the entrails>.

<case and paste> [from "cut and paste"] n. 1. The addition of a new
   <feature> to an existing system by selecting the code from an
   existing feature and pasting it in with minor changes.  Common in
   telephony circles because most operations in a telephone switch are
   selected using case statements.  Leads to <software bloat>.

<cat> [from "concatenate" via <UNIX> `cat(1)'] vt. To spew an entire
   (notionally, large) file to the screen or some other output sink
   without pause; by extension, to dump large amounts of data at an
   unprepared target or with no intention of browsing it carefully.
   Usage: considered silly.  Rare outside UNIX sites.  See also <DD>,

<catatonia> n. A condition of suspended animation in which something
   is so <wedged> that it makes no response.  For example, if you are
   typing on a terminal and suddenly the computer doesn't even echo
   the letters back to the screen as you type, let alone do what
   you're asking it to do, then the computer is suffering from
   catatonia (possibly because it has crashed).

<cdr> /ku'dr/ [from LISP] vt. To remove the first item from a list of
   things.  In the form "cdr down", to trace down a list of
   elements.  "Shall we cdr down the agenda?"  Usage: silly.  See
   also <loop through>.

<chad> /chad/ n. 1. The perforated edge strips on printer paper, after
   they have been separated from the printed portion.  Also called
   <selvage> and <perf>. 2. obs. the confetti-like paper bits punched
   out of cards or paper tape; this was also called `chaff', `computer
   confetti', and `keypunch droppings'.

   Historical note: one correspondent believes `chad' (sense #1)
   derives from the Chadless keypunch (named for its inventor), which
   cut little u-shaped tabs in the card to make a hole when the tab
   folded back, rather than punching out a circle/rectangle; it was
   clear that if the `Chadless' keypunch didn't make them, then the
   stuff that other keypunches made had to be `chad'.

<chain> [orig. from BASIC's CHAIN statement] vi. When used of
   programming languages, refers to a statement that allows a parent
   executable to hand off execution to a child without going through
   the <OS> command interpreter.  The state of the parent program is
   lost and there is no returning to it.  Though this facility used to
   be common on memory-limited micros and is still widely supported
   for backward compatibility, the jargon usage is semi-obsolescent;
   in particular most UNIX programmers will think of this as an
   <exec>.  Oppose the more modern <subshell>.

<char> /keir/ or /char/; rarely, /kar/ n. Shorthand for `character'.
   Esp.  used by C programmers, as `char' is C's typename for
   character data.

<chase pointers> 1. vi. To go through multiple levels of indirection,
   as in traversing a linked list or graph structure.  Used esp. by
   programmers in C, where explicit pointers are a very common data
   type.  This is almost jargon in the strict sense, but remains slang
   when used of human networks. "I'm chasing pointers.  Bob said you
   could tell me who to talk to about..."  2. [Cambridge] <pointer
   chase> or <pointer hunt>: the process of going through a dump
   (interactively or on a large piece of paper printed with hex
   <runes>) following dynamic data-structures.  Only used in a
   debugging context.

<chemist> [Cambridge University] n. Someone who wastes CPU time on
   number-crunching when you'd far rather the CPU was doing something
   more productive, such as working out anagrams of your name or
   printing Snoopy calendars or running <life> patterns.  May or may
   not refer to someone who actually studies chemistry.

<Chernobyl packet> /cher-no'b@l pa'k@t/ n. An IP Ethergram with both
   source and destination Ether and IP address set as the respective
   broadcast address.  So called because it induces <network

<choke> vt. To reject input, often ungracefully.  "I tried building
   <x>, but cpp choked on all those #define's."  See <barf>, <gag>,

<chomp> vt. To lose; to chew on something of which more was bitten off
   than one can.  Probably related to gnashing of teeth.  See
   <bagbiter>.  A hand gesture commonly accompanies this, consisting
   of the four fingers held together as if in a mitten or hand puppet,
   and the fingers and thumb open and close rapidly to illustrate a
   biting action (much like what the PacMan does in the classic video
   game, though this pantomime seems to predate that).  The gesture
   alone means "chomp chomp" (see Verb Doubling).  The hand may be
   pointed at the object of complaint, and for real emphasis you can
   use both hands at once.  For example, to do this to a person is
   equivalent to saying "You chomper!"  If you point the gesture at
   yourself, it is a humble but humorous admission of some failure.
   You might do this if someone told you that a program you had
   written had failed in some surprising way and you felt dumb for not
   having anticipated it.

<chomper> n. Someone or something that is chomping; a loser.  See
   <loser>, <bagbiter>, <chomp>.

<Christmas tree> n. A kind of RS-232 line tester or breakout box
   featuring rows of blinking red and green LEDs like Christmas

<Christmas tree packet> n. A packet with every single option set for
   whatever protocol is in use.

<chrome> [from automotive slang via wargaming] n. Showy features added
   to attract users, but which contribute little or nothing to the
   power of a system. "The 3D icons in Motif are just chrome!"
   Distinguished from <bells and whistles> by the fact that the latter
   are usually added to gratify developers' own desires for

<Church of the Sub-Genius> n. A mutant offshoot of <Discordianism>
   launched in 1981 as a spoof of fundamentalist Christianity by the
   "Rev."  Ivan Stang, a brilliant satirist with a gift for
   promotion.  Popular among hackers as a rich source of bizarre
   imagery and references such as: "Bob" the divine
   drilling-equipment salesman, the Benevolent Space Xists and the
   Stark Fist of Removal.  Much Sub-Genius theory is concerned with
   the acquisition of the mystical substance or quality of "slack".
   See also <ha ha only serious>.

<Classic C> /klas'ik see/ [a play on `Coke Classic'] n.  The C
   programming language as defined in the first edition of <K&R>,
   with some small additions.  It is also known as "K & R C."
   The name came into use during the standardisation process for C by
   the ANSI X3J11 committee.  Also <C Classic>. This is sometimes
   generalized to "X Classic" where X = Star Trek (referring to the
   original TV series), or X = PC (referring to IBM's ISA-bus machines
   as opposed to the PS/2 series); this generalization is especially
   used of product series in which the newer versions are considered
   serious losers relative to the older ones.

<clean> adj. Used of hardware or software designs, implies "elegance
   in the small", that is a design or implementation which may not
   hold any surprises but does things in a way that is reasonably
   intuitive and relatively easy to comprehend from the outside.  The
   antonym is <grungy> or <crufty>.

<CLM> [Sun, "Career Limiting Move"] 1. n. Endangering one's future
   prospects of getting plum projects and raises, also possibly one's
   job.  "He used a bubblesort!  What a CLM!"  2. adj. denoting
   extreme severity of a bug, discovered by a customer and obviously
   due to poor testing: "That's a CLM bug!"

<clobber> v. Mistakenly overwrite.  As in "I walked off the end of
   the array and clobbered the stack."  Compare <mung>, <scribble>,
   <trash>, and <smash the stack>.

<clocks> n. Processor logic cycles, so called because each generally
   corresponds to one clock pulse in the processor's timing.  The
   relative execution times of instructions on a machine are usually
   discussed in `clocks' rather than absolute fractions of a second.
   Compare <cycle>.

<clone> n. 1. An exact duplicate, as in "our product is a clone of
   their product."  Implies a legal re-implementation from
   documentation or by reverse-engineering, as opposed to the
   illegalities under sense #3.  Also connotes lower price.  2. A
   shoddy, spurious copy, as in "their product is a clone of our
   product."  3. A blatant ripoff, most likely violating copyright,
   patent, or trade secret protections, as in "your product is a
   clone of my product."  This usage implies legal action is pending.
   4. A "PC clone"; a PC-BUS/ISA or EISA-compatible 80x86 based
   microcomputer (this use is sometimes spelled "klone").  5. In the
   construction <UNIX clone>: An OS designed to deliver a
   UNIX-lookalike environment sans UNIX license fees, or with
   additional "mission-critical" features such as support for
   real-time programming.

<close> /klohz/ [from the verb "to close", thus the `z' sound] 1. n.
   Abbreviation for "close (or right) parenthesis", used when
   necessary to eliminate oral ambiguity.  See <open>.  2. adj.  Of a
   delimiting character, used at the right-hand end of a grouping.
   Used in such terms as "close parenthesis", "close bracket",
   etc. 3. vt. To release a file or communication channel after

<clustergeeking> /kluh'ster-gee`king/ [CMU] n. An activity defined by
   spending more time at a computer cluster doing CS homework than
   most people spend breathing.

<COBOL> n. Synonomous with <evil>.  Hackers believe all COBOL
   programmers are <suit>s or <code grinder>s, and no self-respecting
   hacker will ever admit to having learned the language.  Its very
   name is seldom uttered without ritual expressions of disgust or

<COBOL fingers> /koh'bol fing'grs/ n. Reported from Sweden, a
   (hypothetical) disease one might get from programming in COBOL.
   The language requires extremely voluminous code.  Programming too
   much in COBOL causes the fingers to wear down (by endless typing),
   until short stubs remain.  This malformity is called "COBOL
   fingers".  "I refuse to type in all that source code again, it
   will give me cobol fingers!"

<code grinder> n. 1. A <suit>-wearing minion of the sort hired in
   legion strength by banks and insurance companies to implement
   payroll packages in RPG and other such unspeakable horrors.  This
   is about as far from hackerdom as you can get and still touch a
   computer.  Connotes pity.  See <Real World>. 2. Used of or to a
   hacker, a really serious slur on the person's creative ability;
   connotes a design style characterized by primitive technique,
   rule-boundedness, and utter lack of imagination.  Compare <card

<code police> [by analogy with "thought police"] n. A mythical team
   of Gestapo-like storm troopers that might burst into one's office
   and arrest one for violating style rules.  May be used either
   seriously, to underline a claim that a particular style violation
   is dangerous, or ironically, to suggest that the practice under
   discussion is condemned mainly by anal-retentive weenies.  The
   ironic usage is perhaps more common.

<codewalker> n. A program component that traverses other programs for
   a living.  Compilers have codewalkers in their front ends; so do
   cross-reference generators and some database front-ends.  Other
   utility programs which try to do too much with source code may turn
   into codewalkers.  As in "This new vgrind feature would require a
   codewalker to implement."

<cokebottle> /kohk'bot-l/ n. Any very unusual character, particularly
   one that isn't on your keyboard so you can't type it.  MIT people
   used to complain about the "control-meta-cokebottle" commands at
   SAIL, and SAIL people complained right back about the
   "altmode-altmode-cokebottle" commands at MIT.  Since the demise
   of the <space-cadet keyboard> this is no longer a serious usage,
   but may be invoked humorously to describe an (unspecified) weird or
   non-intuitive keystroke command.

<COME FROM> n. A semi-mythical language construct dual to the `go to';
   COME FROM <label> would cause the referenced label to act as a sort
   of trapdoor, so that if the program ever reached it control would
   quietly fall through to the statement following the COME FROM.
   COME FROM was first proposed in a Datamation article in 1973 that
   parodied the then-raging `structured programming' wars (see
   <considered harmful>). Mythically, some variants are the "assigned
   come from", and the "computed come from" (parodying some nasty
   control constructs in BASIC and FORTRAN).  Notionally,
   multi-tasking can be implemented by having more than one COME FROM
   statement coming from the same label.

   COME FROM was actually implemented under a different name in
   Univac's Fortran, c.1975.  The statement "AT 100" would perform a
   "COME FROM 100".  It was intended strictly as a debugging aid,
   with dire consequences promised to anyone so deranged as to use it
   in production code.  It was supported under its own name for the
   first time fifteen years later, in C-INTERCAL (see <INTERCAL>,
   <retrocomputing>); knowledgeable observers are still reeling from

<comment out> vt. To surround a section of code with comment
   delimiters in order to prevent it from being compiled.  This may be
   done for a variety of reasons, most commonly when the code is
   redundant or obsolete but you want to leave it in the source to
   make the intent of the active code clearer.

<com[m] mode> /kom mohd/ [from the ITS supporting on-line chat,
   spelled with one or two Ms] Syn. for <talk mode>.

<COMMONWEALTH HACKISH> n. Hacker slang as spoken outside the U.S.,
   esp.  in the British Commonwealth.  It is reported that
   Commonwealth speakers are more likely to pronounce "char",
   "soc" etc. as spelled (/char/, /sok/) as opposed to American
   /keir/ or /sohsh/.  Dots in names tend to be pronounced more often
   (/sok dot wi'bble/ rather than /sohsh wib'ble/).  Preferred
   metasyntactic variables include EEK, OOK, FRODO and BILBO; WIBBLE,
   WOBBLE and in emergencies WUBBLE; BANANA, WOMBAT, FROG, <fish> and
   so on and on.

   Alternatives to verb doubling include suffixes "-o-rama",
   "frenzy" (as in feeding frenzy) and "city" (as in "barf
   city!" "hack-o-rama!" "core dump frenzy!").  Finally, note
   that the American usages `parens' `brackets' and `braces' for (),
   [], and {} are uncommon; Commonwealth hackish prefers
   "bracket", "square bracket" and "curly bracket".  Also, the
   use of "pling" for <bang> is common outside the U.S..

   See also <calculator>, <chemist>, <console jockey>, <fish>,
   <grunge>, <hakspek>, <heavy metal>, <leaky heap>, <lord high
   fixer>, <noddy>, <psychedelicware>, <plingnet>, <raster blaster>,
   <seggie>, <spin-lock>, <terminal junkie>, <tick-list features>,
   <weeble>, <weasel>, <YABA> and notes or definitions under <Bad
   Thing>, <barf>, <bogus>, <bum>, <chase pointers>, <cosmic rays>,
   <crippleware>, <crunch>, <dodgy>, <gonk>, <nybble>, <root>, and

<compress> [UNIX] vt. When used without a qualifier, generally refers
   to <crunch>ing of a file using a particular C implementation of
   Lempel-Ziv compression by James A. Woods et al. and widely
   circulated via <USENET>. Use of <crunch> itself in this sense is
   rare among UNIX hackers.

<computer geek> n.  One who eats [computer] bugs for a living.  One
   who fulfills all of the dreariest negative stereotypes about
   hackers: an asocial, malodorous, pasty-faced monomaniac with all
   the personality of a cheese grater.  Cannot be used by outsiders
   without implied insult to all hackers; compare black-on-black usage
   of "nigger".  A computer geek may be either a fundamentally
   clueless individual or a true-hacker in <larval stage>.  Also
   called "turbo nerd", "turbo geek".  See also <clustergeeking>.

<computron> /kom-pyoo-tron/ n. 1. A notional unit of computing power
   combining instruction speed and storage capacity, dimensioned
   roughly in instructions-per-sec times megabytes-of-main-store times
   megabytes-of-mass-storage.  "That machine can't run GNU Emacs, it
   doesn't have enough computrons!"  This usage is usually found in
   metaphors that treat computing power as a fungible commodity good
   like a crop yield or diesel horsepower.  See <bitty box>, <get a
   real computer>, <toy>, <crank>. 2. A mythical subatomic particle
   that bears the unit quantity of computation or information, in much
   the same way that an electron bears one unit of electric charge
   (see <bogon>).  An elaborate pseudo-scientific theory of computrons
   has been worked out based on the physical fact that the molecules
   in a solid object move more rapidly as it is heated.  It is argued
   that an object melts because the molecules have lost their
   information about where they are supposed to be (that is, they have
   emitted computrons).  This explains why computers get so hot and
   require air conditioning; they use up computrons.  Conversely, you
   should be able to cool down an object by placing it in the path of
   a computron beam.  It is believed that this may also explain why
   machines that work at the factory fail in the computer room ---
   because the computrons there have been all used up by your other

<connector conspiracy> [probably came into prominence with the
   appearance of the KL-10, none of whose connectors match anything
   else] n. The tendency of manufacturers (or, by extension,
   programmers or purveyors of anything) to come up with new products
   which don't fit together with the old stuff, thereby making you buy
   either all new stuff or expensive interface devices.

<cons> /kons/ [from LISP] 1. v. To add a new element to a list, esp.
   at the top.  2.  <cons up>: vt. To synthesize from smaller pieces:
   "to cons up an example".

<considered harmful> adj. Edsger Dijkstra's infamous March 1968 CACM
   note, "Goto Statement Considered Harmful", fired the first salvo
   in the "structured programming" wars.  Amusingly, ACM considered
   the resulting acromony sufficiently harmful that they will (by
   policy) no longer print an article which takes up that assertive a
   position against a coding practice.  In the ensuing decades a large
   number of both serious papers and parodies have borne titles of the
   form "X considered Y".  The "structured programming" wars
   eventually blew over with the realization that both sides were
   wrong, but use of such titles has remained as a persistent minor
   in-joke (the "considered silly" found at various places in this
   jargon file is related).

<console jockey> n.  See <terminal junkie>.

<content-free> adj. Ironic analogy with "context-free", used of a
   message which adds nothing to the recipient's knowledge.  Though
   this adjective is sometimes applied to <flamage>, it more usually
   connotes derision for communication styles which exalt form over
   substance, or are centered on concerns irrelevant to the subject
   ostensibly at hand.  Perhaps most used with reference to speeches
   by company presidents and like animals.  "Content-free?
   Uh...that's anything printed on glossy paper".

<Conway's Law> n. The rule that the organization of the software and
   the organization of the software team will be congruent; originally
   stated as "If you have four groups working on a compiler, you'll
   get a four-pass compiler."

   This was originally promulgated by Melvin Conway, an early
   proto-hacker who wrote an assembler for the Burroughs 220 called
   SAVE.  "SAVE" didn't stand for anything, it was just that you
   lost fewer decks and listings because they all had SAVE written on
   top of them.

<cookie> n. A handle, transaction ID or other form of agreement
   between cooperating programs.  "I give him a packet, he gives me
   back a cookie."  See <magic cookie>.

<cookie monster> [from `Sesame Street'] n. Any of a family of
   early (1970s) hacks reported on <TOPS-10>, <ITS> and elsewhere that
   would lock up either the victim's terminal (on a time-sharing
   machine) or the operator's console (on a batch mainframe),
   repeatedly demanding "I WANT A COOKIE".  The required responses
   ranged in complexity from "COOKIE" through "HAVE A COOKIE" and
   upward.  See also <wabbit>.

<copyleft> /kop'ee-left/ n. 1. The copyright notice ("General Public
   License") carried by <GNU EMACS> and other Free Software
   Foundation software, granting re-use and reproduction rights to all
   comers (but see also <General Public Virus>). 2. By extension, any
   copyright notice intended to achieve similar aims.

<core> n. Main storage or DRAM.  Dates from the days of ferrite-core
   memory; now archaic, but still used in the UNIX community and by
   old-time hackers or those who would sound like same.  See <core

<core dump> n. [UNIX] 1. A symptom of catastrophic program failure due
   to internal error. 2. By extension, used for humans passing out,
   vomiting, or registering extreme shock. "He dumped core.  All over
   the floor.  What a mess." "He heard about ... and dumped core."
   3. Occasionally used for a human rambling on pointlessly at great
   length; esp. in apology: "Sorry I dumped core on you".  4.  A
   recapitulation of knowledge (compare <bits>, sense 1). Hence,
   spewing all one knows about a topic, esp. in a lecture or answer to
   an exam question.  "Short, concise answers are better than core
   dumps" [From the instructions to a qual exam at Columbia].  See

<core leak> n. Syn. with <memory leak>.

<Core Wars> n. A game between "assembler" programs in a simulated
   machine, where the objective is to kill your opponent's program by
   overwriting it.  This was popularized by A.K. Dewdney's column in
   `Scientific American' magazine, but is said to have been first
   devised by Victor Vyssotsky as a PDP-1 hack, during the early '60s
   at Bell Labs.  It is rumored that the game is a civilized version
   of an amusement called DARWIN common on pre-MMU multitasking
   machines.  See <core>.

<corge> /korj/ [originally, the name of a cat] n. Yet another
   meta-syntactic variable, invented by Mike Gallaher and propagated
   by the Gosmacs documentation.  See <grault>.

<cosmic rays> n. Notionally, the cause of <bit rot>.  However, this is
   a semi-independent usage which may be invoked as a humorous way to
   <handwave> away any minor <randomness> that doesn't seem worth the
   bother of investigating. "Hey, Eric --- I just got a burst of
   garbage on my <tube>, where did that come from?" "Cosmic rays, I
   guess". Compare <sunspots>, <phase of the moon>.  The British seem
   to prefer the usage `cosmic showers'; `alpha particles' is also
   heard, because stray alpha particles passing through a memory chip
   can cause single bit errors (this becomes increasingly more likely
   as memory sizes and densities increase).

<cowboy> [Sun, from William Gibson's cyberpunk SF] n. Synonym for
   <hacker>.  It is reported that at Sun, this is often said with

<CP/M> (see-pee-em) [Control Program for Microcomputers] An early
   microcomputer <OS> written by hacker Gary Kildall for 8080 and Z-80
   based machines, very popular in the late 1970s until virtually
   wiped out by MS-DOS after the release of the IBM PC in 1981 (legend
   has it that Kildall's company blew their chance to write the PC's
   OS because Kildall decided to spend the day IBM's reps wanted to
   meet with him enjoying the perfect flying weather in his private
   plane).  Many of its features and conventions strongly resemble
   those of early DEC operating systems such as OS-8, RSTS and RSX-11.
   See <MS-DOS>, <operating system>.

<CPU Wars> n. A 1979 large-format comic by Chas Andres chronicling the
   attempts of the brainwashed androids of "IPM" (Impossible to
   Program Machines) to conquer and destroy the peaceful denizens of
   HEC (Human Engineered Computers).  This rather transparent allegory
   featured many references to <ADVENT> and the immortal line "Eat
   flaming death, minicomputer mongrels!"  (uttered, of course, by an
   IPM stormtrooper). It is alleged that the author subsequently
   received a letter of appreciation on IBM company stationery from
   the then-head of IBM's Thomas J. Watson research laboratories (then
   as now one of the few islands of true hackerdom in the IBM
   archipelago). The lower loop of the `B' in the IBM logo, it is
   said, had been carefully whited out.  See <eat flaming death>.

<cracker> n. One who breaks security on a system.  Coined c.1985 by
   hackers in defense against journalistic misuse of <hacker> (q.v.,
   sense #7).  There had been an earlier attempt to establish "worm"
   in this sense around 1981-1982 on USENET; this largely failed.

<crank> [from automotive slang] vt. Verb used to describe the
   performance of a machine, especially sustained performance. "This
   box cranks about 6 MegaFLOPS, with a burst mode of twice that on
   vectorized operations."

<crash> 1. n. A sudden, usually drastic failure.  Most often said of
   the system (q.v., sense #1), sometimes of magnetic disk drives.
   "Three lusers lost their files in last night's disk crash."  A
   disk crash which entails the read/write heads dropping onto the
   surface of the disks and scraping off the oxide may also be
   referred to as a "head crash", whereas the term "system crash"
   usually, though not always, implies that the operating system or
   other software was at fault.  2. vi. To fail suddenly.  "Has the
   system just crashed?"  Also used transitively to indicate the
   cause of the crash (usually a person or a program, or both).
   "Those idiots playing <SPACEWAR> crashed the system."  3.
   Sometimes said of people hitting the sack after a long <hacking
   run>; see <gronk> (sense #4).

<crash and burn> vi.,n. A spectacular crash, in the mode of the
   conclusion of the car chase scene from Steve McQueen's "Bullitt".
   Sun-3 monitors losing the flyback transformer and lightning strikes
   on VAX-11/780 backplanes are notable crash and burn generators.

<crawling horror> n. Ancient crufty hardware or software that forces
   beyond the control of the hackers at a site refuse to let die.
   Like <dusty deck> or <gonkulator>, but connotes that the thing
   described is not just an irritation but an active menace to health
   and sanity.  "Mostly we code new stuff in C, but they pay us to
   maintain one big Fortran II application from nineteen-sixty-X
   that's a real crawling horror...".  Compare <WOMBAT>.

<cray> /kray/ n. 1. One of the line of supercomputers designed by Cray
   Research.  The term is actually the lowercased last name of Seymour
   Cray, a noted computer architect and co-founder of the company.
   Numerous vivid legends surround him, some true and some admittedly
   invented by Cray Research brass to shape their corporate culture.
   2.  Any supercomputer at all.

<cray instability> n. A shortcoming of a program or algorithm which
   only manifests itself when running a large problem on a powerful
   machine.  Generally more subtle than bugs which can be detected in
   smaller problems running on a workstation or mini.

<crayola> n. A super-mini or -micro computer that provides some
   reasonable percentage of supercomputer performance for an
   unreasonably low price.  Might also be a <killer micro>.

<crayon> n. Someone who works on Cray supercomputers.  More
   specifically implies a programmer, probably of the CDC ilk,
   probably male, and almost certainly wearing a tie (irrespective of
   gender).  Unicos systems types who have a Unix background tend not
   to be described as crayons.

<creeping featuritis> /kree'ping fee-ch@r-ie't@s/ n. 1. Describes a
   systematic tendency to load more <chrome> onto systems at the
   expense of whatever elegance they may have posessed when originally
   designed.  See also <feeping creaturitis>.  "You know, the main
   problem with <BSD UNIX> has always been creeping featuritis".  At
   MIT, this tends to be called "creeping featur*ism*" (and
   likewise, "feeping creaturism"). (After all, -ism means
   "condition" whereas -itis usually means "inflammation of"...)
   2. More generally, the tendency for anything complicated to become
   even more complicated because people keep saying, "Gee, it would
   be even better if it had this feature too."  (See <feature>.)  The
   result is usually a patchwork because it grew one ad-hoc step at a
   time, rather than being planned.  Planning is a lot of work, but
   it's easy to add just one extra little feature to help someone...
   and then another...  and another....  When creeping featurism gets
   out of hand it's like a cancer.  Usually this term is used to
   describe computer programs, but it could also be said of the
   federal government, the IRS 1040 form, and new cars.

<cretin> /kre'tn/ or /kree'tn/ n. Congenital <loser>; an obnoxious
   person; someone who can't do anything right.  It has been observed
   that American hackers tend to favor the British pronunciation
   /kret'n/ over standard American /kreet'n/; it is thought this may
   be due to the insidious phonetic influence of Monty Python's Flying

<cretinous> /kre't@n-us/ or /kree't@n-us/ adj. Wrong;
   non-functional; very poorly designed (Also used pejoratively of
   people).  Synonyms: <bletcherous>, <bagbiter>, <losing>,

<crippleware> n. 1. <shareware> which has some important functionality
   deliberately removed, so as to entice potential users to pay for a
   working version.  See also <guiltware>.  2. [Cambridge] <guiltware>
   which exhorts you to donate to some charity.

<crlf> /ker'l@f/, sometimes /kru'l@f/ n. A carriage return (CR)
   followed by a line feed (LF).  More loosely, whatever it takes to
   get you from the end of one line of text to the beginning of the
   next line.  See <newline>, <terpri>.  Under <UNIX> influence this
   usage has become less common (UNIX uses a bare line feed as its

<crock> [from the obvious mainstream scatologism] n. 1. An awkward
   feature or programming technique that ought to be made cleaner.
   Example: Using small integers to represent error codes without the
   program interpreting them to the user (as in, for example, UNIX
   `make(1)') is a crock.  2. Also, a technique that works acceptably
   but which is quite prone to failure if disturbed in the least, for
   example depending on the machine opcodes having particular bit
   patterns so that you can use instructions as data words too; a
   tightly woven, almost completely unmodifiable structure.  See
   <kluge>.  Also in the adjectives "crockish", "crocky" and the
   noun "crockitude".

<cross-post> [USENET] v.  To post a single article directed to several
   newsgroups.  Distinguished from posting the article repeatedly,
   once to each newsgroup, which causes people to see it multiple
   times.  Cross-posting is frowned upon, as it tends to cause
   followup articles to go to inappropriate newsgroups, as people
   respond to only one part of the original posting (unless the
   originator is careful to specify a newsgroup for followups.)

<crudware> n. Pejorative term for the hundreds of megabytes of
   low-quality <freeware> circulated by user's groups and BBS systems
   in the micro-hobbyist world. "Yet *another* set of disk
   catalog utilities for <MS-DOS>?  What crudware!"  The related usage
   "fuckware" is reported for software so bad it mutilates your
   disk, broadcasts to the Internet, or some similar fiasco.

<cruft> /kruhft/ 1. [back-formation from <crufty>] n. 1. An unpleasant
   substance.  The dust that gathers under your bed is cruft.  2. n.
   The results of shoddy construction.  3. v. [from hand cruft, pun on
   hand craft] to write assembler code for something normally (and
   better) done by a compiler (see <hand-hacking>).  4. Excess;
   superfluous junk.  Esp. used of redundant or superseded code.

<cruft together> /kruhft too-ge'thr/ vt. (also <cruft up /kruhft
   uhp/>) To throw together something ugly but temporarily workable.
   Like v.  <kluge>, but more pejorative.  "There isn't any program
   now to reverse all the lines of a file, but I can probably cruft
   one together in about ten minutes."  See <crufty>.

<cruftsmanship> n. [from <cruft>] The antithesis of craftsmanship.

<crufty> /kruhf'tee/ [origin unknown; poss. from "crusty" or
   "cruddy"] adj. 1.  Poorly built, possibly overly complex.  The
   <canonical> example is "This is standard old crufty DEC
   software".  In fact, one theory of the origin of "crufty" holds
   that was originally a mutation of "crusty" applied to DEC
   software so old that the Ss were tall and skinny, looking more like
   Fs.  Hence <cruft>, n. shoddy construction.  2.  Unpleasant,
   especially to the touch, often with encrusted junk.  Like spilled
   coffee smeared with peanut butter and catsup.  3.  Generally
   unpleasant.  4. <crufty> or <cruftie'> n.  A small crufty object
   (see <frob>); often one which doesn't fit well into the scheme of
   things.  "A LISP property list is a good place to store crufties
   (or, random cruft)."

<crumb> n. Two binary digits; a quad.  Larger than a <bit>, smaller
   than a <nybble>.  Syn. <taste> (sense #2).

<crunch> 1. vi. To process, usually in a time-consuming or complicated
   way.  Connotes an essentially trivial operation which is
   nonetheless painful to perform.  The pain may be due to the
   triviality being imbedded in a loop from 1 to 1000000000.
   "FORTRAN programs do mostly number crunching."  2. vt. To reduce
   the size of a file by a complicated scheme that produces bit
   configurations completely unrelated to the original data, such as
   by a Huffman code.  (The file ends up looking like a paper document
   would if somebody crunched the paper into a wad.)  Since such
   compression usually takes more computations than simpler methods
   such as counting repeated characters (such as spaces) the term is
   doubly appropriate.  (This meaning is usually used in the
   construction "file crunch(ing)" to distinguish it from "number
   crunch(ing)".)  See <compress>.  3. n. The character "#".
   Usage: used at Xerox and CMU, among other places.  See <ASCII>.  4.
   [Cambridge] To squeeze program source into a minimum-size
   representation that will still compile.  The term came into being
   specifically for a famous program on the BBC micro which crunched
   Basic source in order to make it run more quickly (it was a
   wholly-interpretive basic).

<cruncha cruncha cruncha> /kruhn'chah kruhn'chah kruhn'chah/ interj.
   An encouragement sometimes muttered to a machine bogged down in a
   serious <grovel>.  Also describes a notional sound made by
   grovelling hardware.  See <wugga wugga>, <grind> (sense #3).

<cryppie> /krip'ee/ n. A cryptographer.  One who hacks or implements
   cryptographic software or hardware.

<CTSS> /see-tee-ess-ess/ n. Compatible Time-Sharing System.  An early
   (1963) experiment in the design of interactive time-sharing
   operating systems.  Cited here because it was ancestral to
   <Multics>, <UNIX>, and <ITS>.  The name <ITS> ("Incompatible
   Time-sharing System") was a hack on CTSS.

<CTY> /sit'ee/ or /see tee wie/ n. [MIT] The terminal physically
   associated with a computer's operating console.  The term is a
   contraction of "Console TTY", that is, "Console TeleTYpe".
   This <ITS> and <TOPS-10>-associated term has become less common
   than formerly, as most UNIX hackers simply refer to the CTY as `the

<cubing> [parallel with "tubing"] vi. 1. Hacking on an IPSC (Intel
   Personal SuperComputer) hypercube.  "Louella's gone cubing
   *again*!!"  2. An indescribable form of self-torture (see
   sense #1).

<cuspy> /kuhs'pee/ [coined at WPI from the DEC acronym CUSP, for
   Commonly Used System Program, i.e., a utility program used by many
   people] adj. 1.  (of a program) Well-written.  2. Functionally
   excellent.  A program which performs well and interfaces well to
   users is cuspy.  See <rude>.  2. [NYU] An attractive woman,
   especially one regarded as available.

<cybercrud> [coined by Ted Nelson] n. Obfuscatory tech-talk.  Verbiage
   with a high <MEGO> factor.  The computer equivalent of

<cyberpunk> /sie'ber-puhnk/ [orig. by SF critic Gardner Dozois]
   n.,adj.  A subgenre of SF launched in 1982 by William Gibson's
   epoch-making novel `Neuromancer' (though its roots go back
   through Vernor Vinge's `True Names' (See Appendix C) to John
   Brunner's 1975 Hugo winner, `The Shockwave Rider').  Gibson's
   near-total ignorance of computers and the present-day hacker
   culture enabled him to speculate about the role of computers and
   hackers in futures in ways hackers have since found both
   irritatingly naive and tremendously stimulating.  Gibson's work was
   widely imitated, in particular by the short-lived but innovative
   `Max Headroom' TV series.  See <cyberspace>, <ice>, <go

<cyberspace> /sie'ber-spays/ n. Notional "information-space" loaded
   with visual cues and navigable with brain-computer interfaces
   called "cyberspace decks"; a characteristic prop of <cyberpunk>
   SF.  At time of writing (1990) serious efforts to construct
   <virtual reality> interfaces modelled explicitly on <cyberspace>
   are already under way, using more conventional devices such as
   glove sensors and binocular TV headsets.  Few hackers are prepared
   to outright deny the possibility of a cyberspace someday evolving
   out of the network (see <network, the>).

<cycle> n. The basic unit of computation.  What every hacker wants
   more of.  One might think that single machine instructions would be
   the measure of computation, and indeed computers are often compared
   by how many instructions they can process per second, but some
   instructions take longer than others.  Nearly all computers have an
   internal clock, though, and you can describe an instruction as
   taking so many "clock cycles".  Frequently the computer can
   access its memory once on every clock cycle, and so one speaks also
   of "memory cycles".  These are technical meanings of "cycle".
   The slang meaning comes from the observation that there are only so
   many cycles per second, and when you are sharing a computer, the
   cycles get divided up among the users.  The more cycles the
   computer spends working on your program rather than someone else's,
   the faster your program will run.  That's why every hacker wants
   more cycles: so he can spend less time waiting for the computer to

<cycle crunch> n. The situation where the number of people trying to
   use the computer simultaneously has reached the point where no one
   can get enough cycles because they are spread too thin.  Usually
   the only solution is to buy more computer.  Happily, this has
   rapidly become easier in recent years, so much so that the very
   term <cycle crunch> now has a faintly archaic flavor (most hackers
   now use workstations or personal computers as opposed to
   traditional timesharing systems).

<cycle drought> n. A scarcity of cycles.  It may be due to a <cycle
   crunch>, but could also occur because part of the computer is
   temporarily not working, leaving fewer cycles to go around.
   Example: "The <high moby> is <down>, so we're running with only
   half the usual amount of memory.  There will be a cycle drought
   until it's fixed."

<cycle server> n. A powerful machine which exists primarily for
   running large batch jobs.  Interactive tasks such as editing should
   be done on other machines on the network, such as workstations.

                                {= D =}

<daemon> /day'mun/ or /dee'mun/ [Disk And Execution MONitor] n. A
   program which is not invoked explicitly, but which lies dormant
   waiting for some condition(s) to occur.  The idea is that the
   perpetrator of the condition need not be aware that a daemon is
   lurking (though often a program will commit an action only because
   it knows that it will implicitly invoke a daemon).  For example,
   under <ITS> writing a file on the LPT spooler's directory would
   invoke the spooling daemon, which prints the file.  The advantage
   is that programs which want (in this example) files printed need
   not compete for access to the LPT.  They simply enter their
   implicit requests and let the daemon decide what to do with them.
   Daemons are usually spawned automatically by the system, and may
   either live forever or be regenerated at intervals.  Usage:
   <daemon> and <demon> are often used interchangeably, but seem to
   have distinct connotations.  The term <daemon> was introduced to
   computing by <CTSS> people (who pronounced it dee'mon) and used it to
   refer to what ITS called a <dragon>.  The meaning and pronunciation
   have drifted, and we think this glossary reflects current usage.
   See also <demon>.

<DATAMATION> n.  A magazine that many hackers assume all <suits> read.
   Used to question an unbelieved quote, as in "Did you read that in

<day mode> n. See <phase> (of people).

<dd> /dee-dee/ [from IBM <JCL> via] vt. Equivalent to <cat> or <BLT>.
   A specialized UNIX copy command for block-oriented devices.  Often
   used in heavy-handed system abuse, as in "Let's dd the root
   partition onto a tape, then use the boot prom to load it back on to
   a new disk".  The UNIX `dd(1)' was originally written with a weird,
   distinctly non-UNIXy keyword option syntax reminiscent of IBM
   System/360 JCL (which had a similar DD command); though the command
   filled a need, the design choice looks to have been somebody's
   joke.  The slang usage is now very rare outside UNIX sites and now
   nearly obsolescent even there, as `dd(1)' has been <deprecated> for a
   long time (though it has no replacement).  Replaced by <BLT> or
   simple English `copy'.

<DDT> /dee'dee'tee'/ n. 1. Generic term for a program that helps you
   to debug other programs by showing individual machine instructions
   in a readable symbolic form and letting the user change them.  In
   this sense the term DDT is now slightly archaic, having been widely
   displaced by `debugger' 2. [ITS] Under MIT's fabled <ITS> operating
   system, its DDT was also used as the SHELL or top level command
   language used to execute other programs. 3. Any one of several
   specific DDTs (sense 1) supported on early DEC hardware.  The DEC
   PDP-10 Reference Handbook (1969) contained a footnote on the first
   page of the documentation for DDT which illuminates the origin of
   the term:

     Historical footnote: DDT was developed at MIT for the PDP-1
     computer in 1961.  At that time DDT stood for "DEC Debugging
     Tape".  Since then, the idea of an on-line debugging program
     has propagated throughout the computer industry.  DDT programs
     are now available for all DEC computers.  Since media other
     than tape are now frequently used, the more descriptive name
     "Dynamic Debugging technique" has been adopted, retaining
     the DDT acronym.  Confusion between DDT-10 and another well
     known pesticide, dichloro-diphenyl-trichloroethane
     (C14-H9-Cl5) should be minimal since each attacks a different,
     and apparently mutually exclusive, class of bugs.

   Sadly, this quotation was removed from later editions of the
   handbook as the <suit>s took over and DEC became much more

<dead code> n. Code which was once `live' but can never be accessed
   due to changes in other parts of the program.  Syn. <grunge>.

<deadlock> n. 1. A situation wherein two or more processes are unable
   to proceed because each is waiting for another to do something.  A
   common example is a program communicating to a server, which may
   find itself waiting for output from the server before sending
   anything more to it, while the server is similarly waiting for more
   input from the controlling program before outputting anything.  (It
   is reported that this particular flavor of deadlock is sometimes
   called a "starvation" deadlock, though that term is more properly
   used for situations where a program can never run simply because it
   never gets high enough priority.  Another common flavor is
   "constipation", where each process is trying to send stuff to the
   other, but all buffers are full because nobody is reading
   anything.)  See <deadly embrace>.  2. Also used of deadlock-like
   interactions between humans, as when two people meet in a narrow
   corridor, and each tries to be polite by moving aside to let the
   other pass, but they end up swaying from side to side without
   making any progress because they always both move the same way at
   the same time.

<deadly embrace> n. Same as <deadlock>, though usually used only when
   exactly two processes are involved.  This term more popular term in
   Europe; <deadlock> in the United States.  Also "deadly embrace"
   is often restricted to the case where exactly two processes are
   involved, while <deadlock> can involve any number.

<death star> [from the movie `Star Wars'] The AT&T corporate logo,
   which appears on computers sold by AT&T and bears an uncanny
   resemblance to the "Death Star" in the movie.  This usage is
   particularly common among partisans of <BSD> UNIX, who tend to
   regard the AT&T versions as inferior and AT&T as a bad guy.

<DEC Wars> n. A 1983 <USENET> posting by Alan Hastings and Steve Tarr,
   spoofing the `Star Wars' movies in hackish terms.  Some years
   later, ESR (disappointed by Hastings/Tarr's failure to exploit a
   great premise more thoroughly) posted a three-times-longer complete
   rewrite called `UNIX WARS'; the two are often confused.

<deckle> /dek'l/ n. Two <nickle>s; 10 bits.  Reported among developers
   for Mattel's GI 1600 (the Intellivision games processor), a chip
   with 16-bit-wide RAM but 10-bit-wide ROM.

<defenestration> [from the traditional Czechoslovak method of
   assassinating prime ministers, via SF fandom] n. 1. Proper karmic
   retribution for an incorrigible punster. "Oh, ghod, that was
   *awful*!" "Quick! Defenestrate him!"  See also <h infix>.
   2. [proposed] The requirement to support a command-line interface.
   As: "It has to run on a VT100." "Curses! I've been

<defined as> adj. Currently in the role of, usually in an
   off-the-organization-chart sense.  "Pete is currently defined as
   bug prioritizer".

<dehose> vt. To clear a <hosed> condition.

<delint> vt. To modify code to remove problems detected when linting.
   See <lint>.

<demo mode> [Sun] n. State of being <heads down> in order to finish
   code in time for a demo, usually due RSN.

<deep magic> n. An awesomely arcane technique central to a program or
   system, esp. one not generally published and available to hackers
   at large (compare <black art>). one which could only have been
   uttered by a true <wizard>.  Compiler optimization techniques and
   many aspects of <OS> design used to be <deep magic>; many
   techniques in cryptography, signal processing, graphics and AI
   still are.  Compare <heavy wizardry>.  Esp. found in comments of
   the form "Deep magic begins here...".  Compare <voodoo

<deep space> adj. 1. Describes the "location" of any program which
   has gone <off the trolley>.  Esp. used of programs which just sit
   there silently grinding long after either failure or some output is
   expected.  Compare <buzz>, <catatonia>.  2. The metaphorical
   "location" of a human so dazed and/or confused or caught up in
   some esoteric form of <bogosity> that he/she no longer responds
   coherently to normal communication.  Compare <page out>.

<delta> n. 1. A change, especially a small or incremental change.
   Example: "I just doubled the speed of my program!"  "What was
   the delta on program size?"  "About thirty percent."  (He
   doubled the speed of his program, but increased its size by only
   thirty percent.) 2. [UNIX] A <DIFF>, especially a <DIFF> stored
   under the set of version-control tools called SCCS (Source Code
   Control System).  3. n. A small quantity, but not as small as
   <epsilon>.  The slang usage of <delta> and <epsilon> stems from the
   traditional use of these letters in mathematics for very small
   numerical quantities, particularly in so-called "epsilon-delta"
   proofs in the differential calculus.  <delta> is often used once
   <epsilon> has been mentioned to mean a quantity that is slightly
   bigger than <epsilon> but still very small.  For example, "The
   cost isn't epsilon, but it's delta" means that the cost isn't
   totally negligible, but it is nevertheless very small.  Compare
   <within delta of>, <within epsilon of>: that is, close to and even
   closer to.

<demented> adj. Yet another term of disgust used to describe a
   program.  The connotation in this case is that the program works as
   designed, but the design is bad.  For example, a program that
   generates large numbers of meaningless error messages implying it
   is on the point of imminent collapse.

<demigod> n. Hacker with years of experience, a national reputation,
   and a major role in the development of at least one design, tool or
   game used by or known to more than 50% of the hacker community.  To
   qualify as a genuine demigod, the person must recognizably identify
   with the hacker community and have helped shape it.  Major demigods
   include Ken Thompson and Dennis Ritchie (co-inventors of <UNIX> and
   C) and Richard M. Stallman (inventor of <EMACS>).  In their hearts
   of hearts most hackers dream of someday becoming demigods
   themselves, and more than one major software project has been
   driven to completion by the author's veiled hopes of apotheosis.
   See also <net.god>, <true-hacker>.

<demon> n. 1. [MIT] A portion of a program which is not invoked
   explicitly, but which lies dormant waiting for some condition(s) to
   occur.  See <daemon>.  The distinction is that demons are usually
   processes within a program, while daemons are usually programs
   running on an operating system.  Demons are particularly common in
   AI programs.  For example, a knowledge manipulation program might
   implement inference rules as demons.  Whenever a new piece of
   knowledge was added, various demons would activate (which demons
   depends on the particular piece of data) and would create
   additional pieces of knowledge by applying their respective
   inference rules to the original piece.  These new pieces could in
   turn activate more demons as the inferences filtered down through
   chains of logic.  Meanwhile the main program could continue with
   whatever its primary task was. 2. [outside MIT] Often used
   equivalently to <daemon>, especially in the <UNIX> world where the
   latter spelling and pronunciation is considered mildly archaic.

<deprecated> n. Said of a program or feature that is considered
   obsolescent and in the process of being phased out, usually in
   favor of a specified replacement.  Deprecated features can,
   unfortunately, linger on for many years.

<de-rezz, derez> /dee rez/ [from the movie TRON] 1. vi. To disappear
   or dissolve; the image that goes with it is of an object breaking
   up into raster lines and static and then dissolving.  Occasionally
   used of a person who seems to have suddenly "fuzzed out" mentally
   rather than physically.  Usage: extremely silly, also rare.  This
   verb was actually invented as *fictional* hacker slang, and
   adopted in a spirit of irony by real hackers years after the fact.
   2. vt.  On a Macintosh, the data is compiled separately from the
   program, in small segments of the program file known as
   "resources". The standard resource compiler is Rez.  The standard
   resource decompiler is DeRez.  Usage: very common.

<devo> /dee'vo/ [orig. in-house slang at Symbolics] n.  A person in a
   development group.  See also <doco> and <mango>.

<dickless workstation> n. Extremely pejorative hackerism for
   "diskless workstation", a class of botches including the Sun 3/50
   and other machines designed exclusively to network with an
   expensive central disk server.  These combine all the disadvantages
   of time-sharing with all the disadvantages of distributed personal

<diddle> 1. vt. To work with in a not particularly serious manner.
   "I diddled a copy of <ADVENT> so it didn't double-space all the
   time."  "Let's diddle this piece of code and see if the problem
   goes away."  See <tweak> and <twiddle>. 2. n. The action or result
   of diddling.  See also <tweak>, <twiddle>, <frob>.

<diffs> n. 1. Differences, especially difference in source code or
   documents.  Includes additions. "Send me your diffs for the jargon
   file!" 2. (often in the singular <diff>) the output from the
   `diff(1)' utility, esp. when used as specification input to the
   `patch(1)' utility (which can actually perform the mods).  This is a
   common method of distributing patches and source updates in the
   UNIX/C world.

<digit> /dij'it/ n. An employee of Digital Equipment Corporation.  See
   also <VAX>, <VMS>, <PDP-10>, <TOPS-10>, <field circus>.

<dike> vt. To remove or disable a portion of something, as a wire from
   a computer or a subroutine from a program.  A standard slogan runs:
   "When in doubt, dike it out."  (The implication is that it is
   usually more effective to attack software problems by reducing
   complexity rather than increasing it).  The word "dikes" is
   widely used among mechanics and engineers to mean "diagonal
   cutters", a heavy-duty metal-cutting device; to "dike something
   out" means to use such cutters to remove something.  Among hackers
   this term has been metaphorically extended to non-physical objects
   such as sections of code.

<ding> /ding/ n.,vi. 1. Synonym for <feep>.  Usage: rare among
   hackers, but commoner in the <Real World>. 2.  <dinged>: What
   happens when someone in authority gives you a minor bitching about
   something, esp. something you consider trivial.  "I was dinged for
   having a messy desk".

<dink> adj. Said of a machine which has the <bitty box> nature; a
   machine too small to be worth bothering with, sometimes the current
   system you're forced to work on.  First heard from an MIT hacker
   (BADOB) working on a CP/M system with 64K in reference to any 6502
   system, then from people writing 32 bit software about 16 bit
   machines.  "GNUmacs will never work on that dink machine."
   Probably derived from mainstream "dinky", which isn't
   sufficiently perjorative

<dinosaur> n. Any hardware requiring raised flooring and special
   power.  Used especially of old minis and mainframes when contrasted
   with newer microprocessor-based machines.  In a famous quote from
   the '88 UNIX EXPO, Bill Joy compared the mainframe in the massive
   IBM display with a grazing dinosaur, "with a truck outside pumping
   its bodily fluids through it".  IBM was not amused.  Compare <big

<dinosaur pen> n. A traditional mainframe computer room complete with
   raised flooring, special power, its own ultra-heavy-duty air
   conditioning, and a side order of Halon fire extinguishers.  See

<Discordianism> /dis-kor'di-uhn-ism/ n. The veneration of <Eris>, aka
   Discordia; widely popular among hackers.  Popularized by Robert
   Anton Wilson's _Illuminatus!_ trilogy as a sort of self-subverting
   dada-Zen for Westerners --- it should on no account be taken
   seriously but is far more serious than most jokes.  Usually
   connected with an elaborate conspiracy theory/joke involving
   millenia-long warfare between the anarcho-surrealist partisans of
   Eris and a malevolent, authoritarian secret society called the
   Illuminati.  See Appendix B, <Church of the Sub-Genius>, and <ha ha
   only serious>.

<display hack> n. A program with the same approximate purpose as a
   kaleidoscope: to make pretty pictures.  Famous display hacks
   include <munching squares>, <smoking clover>, the BSD UNIX `rain(6)'
   program, `worms(6)' on miscellaneous UNIXes, and the <X> kaleid
   program.  Display hacks can also be implemented without programming
   by creating text files containing numerous escape sequences for
   interpretation by a video terminal; one notable example displayed,
   on any VT100, a Christmas tree with twinkling lights and a toy
   train circling its base.

<doco> /do'ko/ [orig. in-house slang at Symbolics] n.  A documentation
   writer.  See also <devo> and <mango>.

<do protocol> [from network protocol programming] vt.  To perform an
   interaction with somebody or something that follows a clearly
   defined procedure.  For example, "Let's do protocol with the
   check" at a restaurant means to ask the waitress for the check,
   calculate the tip and everybody's share, generate change as
   necessary, and pay the bill.

<dodgy> adj. Syn. with <flaky>.  Preferred outside the U.S.

<dogwash> [From a quip in the "urgency" field of a very optional
   software change request, about 1982.  It was something like,
   "Urgency: Wash your dog first."] n. A project of minimal
   priority, undertaken as an escape from more serious work.  Also, to
   engage in such a project.  Many games and much <freeware> gets
   written this way.

<Don't do that, then!> [from an old doctor's office joke about a
   patient with a trivial complaint] interj. Stock response to a user
   complaint.  "When I type control-S, the whole system comes to a
   halt for thirty seconds."  "Don't do that, then."  Compare

<dongle> /don-gl/ n. 1. A security device for commercial microcomputer
   programs consisting of a serialized EPROM and some drivers in an
   RS-232 connector shell.  Programs that use a dongle query the port
   at startup and programmed intervals thereafter, and terminate if it
   does not respond with the dongle's programmed validation code.
   Thus, users could make as many copies of the program as they want
   but must pay for each dongle.  The idea was clever but initially a
   failure, as users disliked tying up a serial port this way.  Most
   dongles on the market today (1990) will pass data through the port,
   and monitor for "magic codes" (and combinations of status lines)
   with minimal if any interference with devices further down the line
   (this innovation was necessary to allow daisy-chained dongles for
   multiple pieces of software).  The devices are still not widely
   used, as the industry has trended away from copy-protection schemes
   in general. 2. By extension, any physical electronic key or
   transferrable ID required for a program to function.  See

<dongle-disk> /don'gl disk/ n. See <dongle>; a "dongle-disk" is a
   floppy disk with some coding which allows an application to
   identify it uniquely.  It can therefore be used as a <dongle>.
   Also called a "key disk".

<donuts> n. Collective noun for any set of memory bits.  This is
   really archaic and may no longer be live slang; it dates from the
   days of ferrite-core memories in which each bit was represented by
   a doughnut-shaped magnetic flip-flop.  Compare <core>.

<doorstop> n. Used to describe equipment that is non-functional and
   halfway expected to remain so, especially obsolescent equipment
   kept around for political reasons or ostensibly as a backup.
   "When we get another Wyse-50 in here that ADM3 will turn into a
   doorstop."  Compare <boat anchor>.

<dot file> [UNIX] n. A file that is not visible to normal
   directory-browsing tools (on UNIX, files named beginning with a dot
   are normally invisible to the directory lister).

<double bucky> adj. Using both the CTRL and META keys.  "The command
   to burn all LEDs is double bucky F."  See also <meta bit>,
   <cokebottle>, <quadruple bucky>, <space-cadet keyboard>.  The
   following lyrics were written on May 27, 1978, in celebration of
   the Stanford keyboard.  A typical MIT comment was that the Stanford
   <bucky bits> (control and meta shifting keys) were nice, but there
   weren't enough of them; you could only type 512 different
   characters on a Stanford keyword.  An obvious thing was simply to
   add more shifting keys, and this was eventually done; one problem,
   is that a keyboard with that many shifting keys is hard on
   touch-typists, who don't like to move their hands away from the
   home position on the keyboard.  It was half-seriously suggested
   that the extra shifting keys be pedals; typing on such a keyboard
   would be very much like playing a full pipe organ.  This idea is
   mentioned below, in a parody of a very fine song by Jeffrey Moss
   called "Rubber Duckie", which was published in "The Sesame
   Street Songbook".

     			Double Bucky

     	Double bucky, you're the one!
     	You make my keyboard lots of fun.
     	    Double bucky, an additional bit or two:
     	Control and meta, side by side,
     	Augmented ASCII, nine bits wide!
     	    Double bucky!  Half a thousand glyphs, plus a few!
     		I sure wish that I
     		Had a couple of
     		    Bits more!
     		Perhaps a
     		Set of pedals to
     		Make the number of
     		    Bits four:
     		Double double bucky!
     	Double bucky, left and right
     	OR'd together, outta sight!
     	    Double bucky, I'd like a whole word of
     	    Double bucky, I'm happy I heard of
     	    Double bucky, I'd like a whole word of you!

     	--- The Great Quux (with apologies to Jeffrey Moss)

   [This is, by the way, an excellent example of computer <filk> --- ESR]

<doubled sig> /duh'b@ld sig/ [USENET] n.  A <sig block> that has been
   included twice in a <USENET> article or, less frequently, in an
   electronic mail message.  An article or message with a doubled sig
   can be caused by improperly configured software.  More often,
   however, it reveals the author's lack of experience in electronic
   communication.  See <biff>, <pseudo>.

<down> 1. adj. Not operating.  "The up escalator is down."  That is
   considered a humorous thing to say, but "The elevator is down"
   always means "The elevator isn't working" and never refers to
   what floor the elevator is on.  With repect to computers, this
   usage has passed into the mainstream; the extension to other kinds
   of machine is still hackish.  2. <go down> vi. To stop functioning;
   usually said of the <system>.  The message every hacker hates to
   hear from the operator is, "The system will go down in five
   minutes."  3.  <take down>, <bring down> vt. To deactivate
   purposely, usually for repair work. "I'm taking the system down to
   work on that bug in the tape drive."

<download> vt. To transfer data or (esp.) code from a larger `host'
   system (esp. a mainframe) over a digital comm link to a smaller
   `client' system, esp. a microcomputer or specialized peripheral
   device.  Oppose <upload>.

<DP> n. Data Processing.  Listed here because according to hackers,
   use of it marks one immediately as a <suit>.  See <DPer>.

<DPB> /duh-pib'/ [from the PDP-10 instruction set] v., obs. To plop
   something down in the middle.  Usage: silly.  Example: "Dpb
   yourself into that couch, there."  The connotation would be that
   the couch is full except for one slot just big enough for you to
   sit in.  DPB means "DePosit Byte", and was the name of a PDP-10
   instruction that inserts some bits into the middle of some other
   bits.   This usage has been kept alive by the Common Lisp function
   of the same name.

<DPer> n. Data Processor.  Hackers are absolutely amazed that <suits>
   use this term self-referentially. "*Computers* process data,
   not people!"  See <DP>.

<dragon> n. [MIT] A program similar to a <daemon>, except
   that it is not invoked at all, but is instead used by the system to
   perform various secondary tasks.  A typical example would be an
   accounting program, which keeps track of who is logged in,
   accumulates load-average statistics, etc.  Under ITS, many
   terminals displayed a list of people logged in, where they are,
   what they're running, etc. along with some random picture (such as
   a unicorn, Snoopy, or the Enterprise) which was generated by the
   "name dragon".  Usage: rare outside MIT --- under UNIX and most
   other OSs this would be called a `background <demon>' or <daemon>.
   The best-known UNIX example of a dragon is `cron(1)'.  At SAIL they
   called this sort of thing a "phantom".

<Dragon Book> n. Aho, Sethi and Ullman's classic compilers text
   `Principles Of Compiler Design', so called because of the cover
   design depicting a knight slaying a dragon labelled "compiler
   complexity".  This actually describes the "Red Dragon Book"; an
   earlier edition (sans Sethi) was the "Green Dragon Book".  See
   also <Blue Book>, <Red Book>, <Green Book>, <Silver Book>, <Purple
   Book>, <Orange Book>, <White Book>, <Pink-Shirt Book>, <Aluminum

<drain> [IBM] v. Syn. for <flush> (sense 4).

<dread high bit disease> n. A condition endemic to PRIME (formerly
   PR1ME) minicomputers which results in all the characters having
   their high (0x80) bit ON rather than OFF.  This of course makes
   transporting files to other systems much more difficult, not to
   mention talking to true eightbit devices.  It is reported that
   PRIME adopted the reversed eight bit convention in order to save 25
   cents/serial line/machine.  This probably qualifies as one of the
   most <cretinous> design tradeoffs ever made.  See <meta bit>.

<DRECNET> /drek'net/ [fr. Yiddish `dreck'] n. Deliberate distortion of
   DECNET, a networking protocol used in the VMS community.  So-called
   because DEC helped write the Ethernet specification, and then
   (either stupidly or as a malignant customer-control tactic)
   violated that spec in the design of DRECNET (among other things,
   they implemented the wrong <heartbeat> speed). See also <connector

<drool-proof paper> n. Documentation which has been obsessively dumbed
   down, to the point where only a <cretin> could bear to read it, is
   said to have succumbed to the "drool-proof paper syndrome" or to
   have been "written on drool-proof paper".  For example, this is
   an actual quote from Apple's LaserWriter manual: "Do not expose
   your LaserWriter to open fire or flame."

<drop on the floor> vt. To react to an error condition by silently
   discarding messages or other valuable data.  Example: "The gateway
   ran out of memory, so it just started dropping packets on the
   floor."  Also frequently used of faulty mail and netnews relay
   sites that lose messages.  See also <black hole>.

<drugged> adj., also "on drugs".  1. Conspicuously stupid, heading
   towards <brain-damaged>.  Often accompanied by a pantomime of
   toking a joint.  2. Of hardware, very slow relative to normal

<drunk mouse syndrome> n.  A malady exhibited by the mouse pointing
   device of some workstations.  The typical symptom is for the mouse
   cursor on the screen to move to random directions and not in sync
   with the moving of the actual mouse.  Can usually be corrected by
   unplugging the mouse and plugging it back again.  Another
   recommended fix is to rotate your optical mouse pad 90 degrees.

<dumbass attack> /duhm'ass @-tak'/ [Purdue] n. A novice's mistake
   made by the experienced, especially one made by running as root
   under UNIX, e.g. typing "rm *" or mkfs on a mounted file system.
   Compare <adger>.

<dusty deck> n. Old software (especially applications) with which one
   is obliged to remain compatible.  The term implies that the
   software in question is a holdover from card-punch days.  Used esp.
   when referring to old scientific and number-crunching software,
   much of which was written in FORTRAN and very poorly documented but
   would be too expensive to replace.  See <fossil>.

<DWIM> /dwim/ [Do What I Mean] 1. adj. Able to guess, sometimes even
   correctly, what result was intended when provided with bogus input.
   Often suggested in jest as a desired feature for a complex program;
   also occasionally described as the single instruction the ideal
   computer would have (back when proof of program correctness were in
   vogue, there were also jokes about <DWIMC>: Do What I Mean,
   Correctly).  A related term, more often seen as a verb, is DTRT (Do
   The Right Thing), see <Right Thing, The>.  2. n.,obs. The INTERLISP
   function that attempted to accomplish this feat by correcting many
   of the more common errors.  See <hairy>.

<dynner> /din'r/ 32 bits, by analogy with <nybble> and byte.  Usage:
   rare and extremely silly.  See also <playte>, <taste>, <crumb>.

                                {= E =}

<earthquake> [IBM] n. The ultimate real-world shock test for computer
   hardware.  Hacker sources at IBM deny the rumor that the Bay Area
   quake of 1989 was initiated by the company to test QA at its
   California plants.

<Easter egg> n. 1. A message hidden in the object code of a program as
   a joke, intended to be found by persons disassembling or browsing
   the code. 2. A message, graphic, or sound-effect emitted by a
   program (or, on a PC, the BIOS ROM) in response to some
   undocumented set of commands or keystrokes, intended as a joke or
   to display program credits.  One well-known early Easter egg found
   in a couple of OSs caused them to respond to the command `make
   love' with `not war?'.  Many personal computers (other than the IBM
   PC) have much more elaborate eggs hidden in ROM, including lists of
   the developers' names, political exhortations, snatches of music,
   and (in one case) graphics images of the entire development team.

<Easter egging> [IBM] n. The act of replacing unrelated parts more or
   less at random in hopes that a malfunction will go away.  Hackers
   consider this the normal operating mode of <field circus> techs and
   do not love them for it.

<eat flaming death> imp. A construction popularized among hackers by
   the infamous <DEC WARS> comic; supposed to derive from a famously
   turgid line in a WWII-era anti-Nazi propaganda comic in which X was
   "non-Aryan mongrels" or something of the sort.  Used in
   humorously overblown expressions of hostility. "Eat flaming death,
   EBCDIC users!"

<eighty-column mind> [IBM] n. The sort said to be employed by persons
   for whom the transition from card to tape was traumatic (nobody has
   dared tell them about disks yet).  It is said that these people,
   like (according to an old joke) the founder of IBM, will be buried
   `9-EDGE-FORWARD-FACE-DOWN'.  These people are thought by most
   hackers to dominate IBM's customer base, and its thinking.

<El Camino Bignum> /el' k@-mee'noh big'num/ n. El Camino Real.  El
   Camino Real is the name of a street through the San Francisco
   peninsula that originally extended (and still appears in places)
   all the way down to Mexico City.  Navigation on the San Francisco
   peninsula is usually done relative to El Camino Real, which is
   assumed to run north and south even though it doesn't really in
   many places (see <logical>).  El Camino Real runs right past
   Stanford University, and so is familiar to hackers.  The Spanish
   word "real" (which has two syllables (ray-ahl')) means "royal";
   El Camino Real is "the royal road".  Now the English word
   "real" is used in mathematics to describe numbers (and by analogy
   is misused in computer jargon to mean floating-point numbers).  In
   the FORTRAN language, for example, a "real" quantity is a number
   typically precise to seven decimal places, and a "double
   precision" quantity is a larger floating-point number, precise to
   perhaps fourteen decimal places.  When a hacker from MIT visited
   Stanford in 1976 or so, he remarked what a long road El Camino Real
   was.  Making a pun on "real", he started calling it "El Camino
   Double Precision" --- but when the hacker was told that the road
   was hundreds of miles long, he renamed it "El Camino Bignum", and
   that name has stuck.  (See <bignum>.)

<elegant> [from mathematical usage] adj. Combining simplicity, power,
   and a certain ineffable grace of design.  Higher praise than
   `clever', `winning' or even <cuspy>.

<elephantine> adj. Used of programs or systems which are both
   conspicuous <hog>s (due perhaps to poor design founded on <brute
   force and ignorance>) and exceedingly <hairy> in source form.  An
   elephantine program may be functional and even friendly, but (like
   the old joke about being in bed with an elephant) it's tough to
   have around all the same, esp. a bitch to maintain.  In extreme
   cases, hackers have been known to make trumpeting sounds or perform
   expressive zoomorphic mime at the mention of the offending program.
   Usage: semi-humorous.  Compare "has the elephant nature" and the
   somewhat more pejorative <monstrosity>.  See also <second-system
   effect> and <baroque>.

<EMACS> /ee'maks/ [from Editing MACroS] n. The ne plus ultra of hacker
   editors, a program editor with an entire LISP interpreter inside
   it.  Originally written by Richard Stallman in <TECO> at the MIT-AI
   lab, but the most widely used versions now run under UNIX.  It
   includes facilities to run compilation subprocesses and send and
   receive mail; many hackers spend up to 80% of their tube time
   inside it.  Some versions running under window managers iconify as
   a kitchen sink, perhaps to suggest the one feature the editor
   doesn't include.  Indeed, some hackers find EMACS too heavyweight
   and baroque for their taste, and expand the name as "Escape Meta
   Alt Control Shift" to spoof its heavy reliance on complex
   bucky-bitted keystrokes.  Other spoof expansions include Eight
   Megabytes And Constantly Swapping, Eventually malloc()s All
   Computer Storage, and EMACS Makes A Computer Slow (see <RECURSIVE
   ACRONYMS>).  See also <vi>.

<email> /ee-mayl/ vt.,n. Electronic mail automatically passed through
   computer networks and/or via modems common-carrier lines.  Contrast
   <snail-mail>.  See <network address>.

<emoticon> /ee-moh'ti-cahn/ n. An ASCII glyph used to indicate an
   emotional state in email or news.  Hundreds have been proposed, but
   only a few are in common use.  These include:

     :-) Smiley face (indicates laughter)
     :-( Frowney face (indicates sadness, anger or upset)
     ;-) Half-smiley (ha ha only serious)
         Also known as "semi-smiley" or "winkey face".
     :-/ Wry face

   Of these, the first two are by far the most frequently encountered.
   Hyphenless forms of them are common on CompuServe, GEnie and BIX;
   see also <bixie>.  On <USENET>, "smiley" is often used as a
   generic (synonym for emoticon) as well as specifically for the
   happy-face emoticon.

   Note for the <newbie>: overuse of the smiley is a mark of
   loserhood!  More than one per paragraph is a fairly sure sign that
   you've gone over the line.

<empire> n. Any of a family of military simulations derived from a
   game written by Peter Langston many years ago.  There are 5 or 6
   multi-player variants of varying degrees of sophistication, and one
   single-player version implemented for both UNIX and VMS which is
   even available as MS-DOS freeware.  All are notoriously addictive.

<English> /ing'lish/ n.,obs. The source code for a program, which may
   be in any language, as opposed to <binary>.  The idea behind the
   term is that to a real hacker, a program written in his favorite
   programming language is as readable as English.  Usage: obsolete,
   used mostly by old-time hackers, though recognizable in context.

<ENQ> /enkw/ [from the ASCII mnemonic for 0000101] 1. An on-line
   convention for querying someone's availability.  After opening a
   <talk mode> connection to someone apparently in heavy hack mode,
   one might type "SYN SYN ENQ?" (the SYNs representing notional
   synchronization bytes) expecting a return of <ACK> or NAK depending
   on whether or not the person felt interruptible.  See <ACK>;
   compare <ping>, <finger>, and the usage of `FOO?' listed under
   <talk mode>.

<EOF> /ee-oh-ef/ [UNIX/C] n. End Of File. 1. Refers esp. to whatever
   pseudo-character value is returned by C's sequential input
   functions (and their equivalents in other environments) when the
   logical end of file has been reached (this was 0 under V6 UNIX, is
   -1 under V7 and all subsequent versions and all non-UNIX C library
   implementations). 2. Used by extension in non-computer contexts
   when a human is doing something that can be modelled as a
   sequential read and can't go further. "Yeah, I looked for a list
   of 360 mnemonics to post as a joke, but I hit <EOF> pretty fast,
   all the library had was a JCL manual."

<EOU> /ee oh yoo/ The mnemonic of a mythical ASCII control character
   (End Of User) that could make a Model 33 Teletype explode on
   receipt.  This parodied the numerous obscure record-delimiter
   control characters left in ASCII from the days when it was more
   associated with wire-service teletypes than computers (e.g. FS, GS,
   RS, US, EM, SUB, ETX and esp. EOT).  It is worth remembering that
   ASR-33s were big, noisy mechanical beasts with a lot of clattering
   parts; the notion that one might explode was nowhere near as
   ridiculous as it might seem to someone sitting in front of a <tube>
   or flatscreen today.

<epoch, the> [UNIX] n. The time and date corresponding to zero in an
   operating system's clock and timestamp values.  Under most UNIX
   versions, 00:00 of January 1st 1970 GMT.  System time is measured
   in seconds or <tick>s past the epoch.  See <tick>s, <wall time>.
   Note that weird problems may ensue when the clock wraps around (see
   <wrap around>), and that this is not a necessarily a rare event; on
   systems counting 10 <tick>s per second, a 32 bit count of ticks is
   only good for 6.8 years.  The 1-per-second clock of UNIX is good
   until January 18, 2038, assuming word lengths don't increase by

<epsilon> [from standard mathematical notation for a small quantity]
   1.  n. A small quantity of anything.  "The cost is epsilon."  2.
   adj.  Very small, negligible; less than marginal.  "We can get
   this feature for epsilon cost."  3. <within epsilon of>: close
   enough to be indistinguishable for all practical purposes.  this is
   even closer than being <within delta of>.  Example: "That's not
   what I asked for, but it's within epsilon of what I wanted."
   Alternatively, it may mean not close enough, but very little is
   required to get it there: "My program is within epsilon of
   working."  See <asymptotic>.

<epsilon squared> n. A quantity even smaller than <epsilon>, as small
   in comparison to it as it is to something normal.  If you buy a
   supercomputer for a million dollars, the cost of the
   thousand-dollar terminal to go with it is <epsilon>, and the cost
   of the ten-dollar cable to connect the two is <epsilon squared>.

<era, the> Syn. <epoch>.  The Webster's Unabridged makes these words
   almost synonymous, but "era" usually connotes a span of time
   rather than a point in time.  The <epoch> usage is recommended.

<Eric Conspiracy> n. Notional group of mustachioed hackers named Eric
   first pinpointed as a sinister conspiracy by an infamous
   talk.bizarre posting c. 1986; this was doubtless influenced by the
   numerous `Eric' jokes in the Monty Python oeuvre.  There do indeed
   seem to be considerably more mustachioed Erics in hackerdom than
   the frequency of these three traits can account for unless they are
   correlated in some arcane way.  Well known examples include Eric
   Allman of <BSD> fame, Erik Fair (coauthor of NNTP); your editor has
   heard from about fourteen others by email, and the organization
   line `Eric Conspiracy Secret Laboratories' now emanates regularly
   from more than one site.

<Eris> /e'r@s/ pn. The Greco-Roman goddess of Chaos, Discord,
   Confusion and Things You Know Not Of; aka Discordia.  Not a very
   friendly deity in the Classical original, she was re-invented as a
   more benign personification of creative anarchy starting in 1959 by
   the adherents of <Discordianism> and has since been a semi-serious
   subject of veneration in several `fringe' cultures including
   hackerdom.  See <Discordianism>, <Church of the Sub-Genius>.

<erotics> /ee-ro'tiks/ n. Reported from Scandinavia as
   English-language university slang for electronics.  Often used by
   hackers, maybe because of its exciting aspects.

<essentials> n. Things necessary to maintain a productive and secure
   hacking environment. "A jug of wine, a loaf of bread, a
   20-megahertz 80386 box with 8 meg of core and a 300-megabyte disk
   supporting full UNIX with source and X windows and EMACS and UUCP
   to a friendly Internet site, and thou."

<evil> adj. As used by hackers, implies that some system, program,
   person or institution is sufficiently mal-designed as to be not
   worth the bother of dealing with.  Unlike the adjectives in the
   <cretinous>/<losing>/<brain-damaged> series, "evil" does not
   imply incompetence or bad design, but rather a set of goals or
   design criteria fatally incompatible with the speaker's.  This is
   more an esthetic and engineering judgement than a moral one in the
   mainstream sense. "We thought about adding a <Blue Glue> interface
   but decided it was too evil to deal with." "<TECO> is neat, but
   it can be pretty evil if you're prone to typos."  Often pronounced
   with the first syllable lengthened, as /eeeevil/.

<exa-> /ex'ga/ pref. See <kilo>.

<examining the entrails> n. The process of rooting through a core dump
   or hex image in the attempt to discover the bug that brought your
   program or system down.  Compare <runes>, <incantation>, <black

<EXCH> /eks'ch@, ekstch/ vt. To exchange two things, each for the
   other; to swap places.  If you point to two people sitting down and
   say "Exch!", you are asking them to trade places.  <EXCH>,
   meaning EXCHange, was originally the name of a PDP-10 instruction
   that exchanged the contents of a register and a memory location.
   Many newer hackers tend to be thinking instead of of the Postscript
   exchange operator.

<excl> /eks'kl/ n. Abbreviation for "exclamation point".  See
   <bang>, <shriek>, <wow>.

<EXE> /ex'ee/ An executable binary file.  Some operating systems
   (notably MS-DOS and VMS) use the extension .EXE to mark such files.
   This usage is also occasionally found among UNIX programmers even
   though UNIX executables don't have any required extension (in fact,
   the term "extension" in this sense is not part of UNIX jargon).

<exec> /eg'zek/ [shortened from "executive" or "execute"] vt.,n.
   1.  [UNIX] Synonym for <chain>, derives from the `exec(2)' call. 2.
   (obs) The command interpreter for an <OS> (see <shell>); term esp.
   used on mainframes, and prob. derived from UNIVAC's archaic EXEC 2
   and EXEC 8 operating systems.

<exercise, left as an> [Technical reference books] Used to complete a
   proof when one doesn't mind a <handwave>, or to avoid one entirely.
   The complete phrase is: "The proof (or rest) is left as an
   exercise for the reader."

                                {= F =}

<fall over> [IBM] vi. Yet another synonym for <crash> or <lose>.
   `Fall over hard' equates to <crash and burn>.

<fall through> vt. 1. To exit a loop by exhaustion, i.e. by having
   fulfilled its exit condition rather than via a break or exception
   condition that exits from the middle of it.  This usage appears to
   be *really* old, as in dating from the '40s and '50s.  It may
   no longer be live slang.  2.  To fail a test that would have passed
   control to a subroutine or other distant portion of code.  2. In C,
   `fall-through' is said to occur when the flow of execution in a
   switch statement reaches a `case' label other than by jumping there
   from the switch header, passing a point where one would normally
   expect to find a `break'. A trivial example:

     switch (color)
     case GREEN:
     case PINK:
     case RED:

   The effect of this code is to do_green() when color is GREEN,
   do_red() when color is RED, do_blue() on any other color than PINK,
   and (this is the important part) do_pink() and *then* do_red()
   when color is PINK.  Fall-through is <considered harmful> by some;
   among those who use it, it is considered good practice to include a
   comment highlighting the fall through, at the point one would
   normally expect a break.

<fandango on core> [UNIX/C hackers, from the Mexican dance] n. In C, a
   wild pointer that runs out of bounds causing a <core dump>, or
   corrupts the `malloc(3)' <arena> in such a way as to cause mysterious
   failures later on, is sometimes said to have `done a fandango on
   core'.  On low-end personal machines without an MMU this can
   corrupt the OS itself, causing massive lossage.  Other third-world
   dances such as the rhumba, cha-cha or watusi may be substituted.
   See <aliasing bug>, <precedence lossage>, <smash the stack>,
   <memory leak>, <overrun screw>, <core>.

<FAQ list> /ef-ay-kyoo list/ [Usenix] n. Compendium of accumulated
   lore, posted periodically to high-volume newsgroups in an attempt
   to forestall Frequently Asked Questions.  The jargon file itself
   serves as a good example of a collection of one kind of lore,
   although it is far too big for a regular posting.  Several extant
   FAQ lists do (or should) make reference to the jargon file.  "How
   do you pronounce `char'?" and "What's that funny name for the `#'
   character?" are, for example, both Frequently Asked Questions.

<farming> [Adelaide University, Australia] n. What the heads of a
   Winchester are said to do when the plow little furrows in the
   magnetic media.  Associated with a <crash>.  Typically used as
   follows: "Oh no, the machine has just crashed, I hope the hard
   drive hasn't gone <farming> again."

<fascist> adj. Said of a computer system with excessive or annoying
   security barriers, usage limits or access policies.  The
   implication is that said policies are preventing hackers from
   getting interesting work done.  The variant "fascistic" seems to
   have been preferred at MIT, poss. by analogy with "touristic"
   (see <tourist>).

<faulty> adj. Non-functional; buggy.  Same denotation as
   "bagbiting", "bletcherous", "losing", q.v., but the
   connotation is much milder.

<fd leak> /ef dee leek/ n. A kind of programming bug analogous to a
   <core leak>, in which a program fails to close file descriptors
   ("fd"s) after file operations are completed, and thus eventually
   runs out.  See <leak>.

<fear and loathing> [from Hunter Thompson] n. State inspired by the
   prospect of dealing with certain real-world systems and standards
   which are totally <brain-damaged> but ubiquitous --- Intel 8086s,
   or COBOL, or any IBM machine except the Rios (aka the RS/6000).
   "Ack.  They want PCs to be able to talk to the AI machine.  Fear
   and loathing time!"  See also IBM.

<feature> n.  1. An intended property or behavior (as of a program).
   Whether it is good or not is immaterial.  2. A good property or
   behavior (as of a program).  Whether it was intended or not is
   immaterial.  3. A surprising property or behavior; in particular,
   one that is purposely inconsistent because it works better that
   way.  For example, in some versions of the <EMACS> text editor, the
   "transpose characters" command exchanges the two characters on
   either side of the cursor on the screen, *except* when the
   cursor is at the end of a line, in which case the two characters
   before the cursor are exchanged.  While this behavior is perhaps
   surprising, and certainly inconsistent, it has been found through
   extensive experimentation to be what most users want; the
   inconsistency is therefore a <feature> and not a <bug>.  4. A
   property or behavior that is gratuitous or unnecessary, though
   perhaps also impressive or cute.  For example, one feature of the
   MACLISP language is the ability to print numbers as Roman numerals.
   See <bells and whistles>.  5. A property or behavior that was put
   in to help someone else but that happens to be in your way. 6. A
   <bug> that has been documented.  To call something a feature
   sometimes means the author of the program did not consider the
   particular case, and the program responded in a way that was
   unexpected, but not strictly incorrect.  A standard joke is that a
   <bug> can be turned into a <feature> simply by documenting it (then
   theoretically no one can complain about it because it's in the
   manual), or even by simply declaring it to be good.  "That's not a
   bug, that's a feature!"  See also <feetch feetch>.

<feature creature> n. One who loves to add features to designs or
   programs, perhaps at the expense of coherence, concision, or
   <taste>.  See also <creeping featurism>.

<featurectomy> /fee`ch@r-ek'to-mee/ n. The act of removing a feature
   from a program.  Featurectomies generally come in two varieties,
   the "righteous" and the "reluctant".  Righteous featurectomies
   are performed because the remover believes the program would be
   more elegant without the feature, or there is already an equivalent
   and "better" way to achieve the same end.  (This is not quite the
   same thing as removing a <misfeature>.)  Reluctant featurectomies
   are performed to satisfy some external constraint such as code size
   or execution speed.

<feep> /feep/ 1. n. The soft bell of a display terminal (except for a
   VT-52!); a beep (in fact, the microcomputer world seems to prefer
   <beep>).  2. vi. To cause the display to make a feep sound.  TTY's
   do not have feeps; they have mechanical bells that ring.  Alternate
   forms: <beep>, <bleep>, or just about anything suitably
   onomatopoeic.  (Jeff Macnelly, in his comic strip `Shoe', uses
   the word `eep' for sounds made by computer terminals and video
   games; this is perhaps the closest written approximation yet.)  The
   term <beedle> was sometimes heard at SAIL, where the terminal
   bleepers are not particularly "soft" (they sound more like the
   musical equivalent of a raspberry or Bronx cheer; for a close
   approximation, imagine the sound of a Star Trek communicator's beep
   lasting for five seconds.).  The "feeper" on a VT-52 has been
   compared to the sound of a '52 Chevy stripping its gears.  See also

<feeper> /fee'pr/ n. The device in a terminal or workstation (usually
   a loudspeaker of some kind) that makes the <feep> sound.

<feeping creaturitis> /fee'ping kree`ch@r-ie'tis/ n. Deliberate
   spoonerization of <creeping featuritis>, meant to imply that the
   system or program in question has become a misshapen creature of
   hacks.This term isn't really well-defined, but it sounds so neat
   that most hackers have said or heard it.  It is probably reinforced
   by an image of terminals prowling about in the dark making their
   customary noises.

<feetch feetch> interj.  If someone tells you about some new
   improvement to a program, you might respond, "Feetch, feetch!"
   The meaning of this depends critically on vocal inflection.  With
   enthusiasm, it means something like, "Boy, that's great!  What a
   great hack!"  Grudgingly or with obvious doubt, it means "I don't
   know; it sounds like just one more unnecessary and complicated
   thing."  With a tone of resignation, it means, "Well, I'd rather
   keep it simple, but I suppose it has to be done."

<fencepost error> n. 1. The discrete equivalent of a boundary
   condition.  Often exhibited in programs by iterative loops.  From
   the following problem: "If you build a fence 100 feet long with
   posts ten feet apart, how many posts do you need?"  (Either 9 or
   11 is a better answer than the obvious 10.)  For example, suppose
   you have a long list or array of items, and want to process items m
   through n; how many items are there?  The obvious answer is n - m,
   but that is off by one; the right answer is n - m + 1.  A program
   that used the "obvious" formula would have a fencepost error in
   it.  See also <off-by-one error>, and note that not all off-by-one
   errors are fencepost errors.  The game of Musical Chairs involves
   an off-by-one problem where N people try to sit in N-1 chairs, but
   it's not a fencepost error.  Fencepost errors come from counting
   things rather than the spaces between them, or vice versa, or by
   neglecting to consider whether one should count one or both ends of
   a row.  2.  Occasionally, an error induced by unexpectedly regular
   spacing of inputs, which can (for instance) screw up your hash

<field circus> [a derogatory pun on "field service"] n.  The field
   service organization of any hardware manufacturer, but especially
   DEC.  There is an entire genre of jokes about DEC field circus

     Q: How can you recognize a DEC field circus engineer with a flat tire?
     A: He's changing each tires to see which one is flat.

     Q: How can you recognize a DEC field circus engineer who is out of
     A: He's changing each tires to see which one is flat.

<field servoid> /fee'@ld ser'void/ n. Representative of a Field Service
   organisation (see <field circus>).

<filk> /filk/ [from SF fandom, where a typo for "folk" was adopted
   as a new word] n.,v. A "filk" is a popular or folk song with
   lyrics revised or completely new lyrics, intended for humorous
   effect when read and/or to be sung late at night at SF conventions.
   There is a flourishing subgenre of these called "computer filks",
   written by hackers and often containing technical humor of quite
   sophisticated nature.  See <double bucky> for an example.

<film at 11> [MIT, in parody of TV newscasters], interj.  Used in
   conversation to announce ordinary events, with a sarcastic
   implication that these events are earth-shattering. "<ITS>
   crashes; film at 11." "Bug found in scheduler; film at 11."

<filter> [orig. UNIX, now also in <MS-DOS>] n. A program which
   processes an input text stream into an output text stream in some
   well-defined way, and does no I/O to anywhere else except possibly
   on error conditions; one designed to be used as a stage in a

<fine> [WPI] adj. Good, but not good enough to be <cuspy>.  The word
   "fine" is used elsewhere, of course, but without the implicit
   comparison to the higher level implied by <cuspy>.

<finger> [SAIL's mutant TOPS-10, via BSD UNIX] 1. n. A program that
   displays a particular user or all users logged on the system or a
   remote system.  Typically shows full name, last login time, idle
   time, terminal line and terminal location.  May also display a
   "plan file" left by the user. 2.  vt.  To apply finger to a
   username. 3.  vt. By extension, to check a human's current state by
   any means.  "Foodp?"  "T!"  "OK, finger Lisa and see if she's
   idle".  4.  Any picture (composed of ASCII characters) depicting
   "the finger".  Originally a humorous component of one's "plan
   file" to deter the curious fingerer (sense #2), it has entered the
   arsenal of some <flamer>s.

<firebottle> n. A large, primitive, power-hungry active electrical
   device, similar to an FET constructed out of glass, metal, and
   vacuum.  Characterized by high cost, low density, low reliability,
   high-temperature operation, and high power dissipation.  Sometimes
   mistakenly called a "tube" in the U.S. or a "valve" in England.

<firefighting> n. The act of throwing lots of manpower and late nights
   at a project to get it out before deadline.  See also <gang bang>;
   however, <firefighting> connotes that the effort is going into
   chasing bugs rather than adding features.

<firewall machine> n. A dedicated gateway machine with special
   security precautions on it, used to service outside
   network/mail/news connections and/or accept remote logins for (read
   only) shared-file-system access via FTP.  The idea is to protect a
   cluster of more loosely administered machines `hidden' behind it
   from crackers.  The typical `firewall' is an inexpensive
   micro-based UNIX box kept clean of critical data, with a bunch of
   modems and public network ports on it but just one carefully
   watched connection back to the rest of the cluster.  The special
   precautions may include threat monitoring, callback, and even a
   complete <iron box> keyable to particular incoming IDs or activity
   patterns.  Syn. <flytrap>, <venus flytrap>.

<fireworks mode> n. The mode a machine is sometimes said to be in when
   it is performing a <crash and burn> operation.

<firmware> n. Software installed into a computer-based piece of
   equipment on ROM. So-called because it's harder to change than
   software but easier than hardware.

<fish> [Adelaide University, Australia] n. Another metasyntactic
   variable.  See <foo>.  Derived originally from the Monty-Python
   skit in the middle of "The Meaning of Life", entitled "Find the

<flag> n. A variable or quantity that can take on one of two values; a
   bit, particularly one that is used to indicate one of two outcomes
   or is used to control which of two things is to be done.  Examples:
   "This flag controls whether to clear the screen before printing
   the message."  "The program status word contains several flag
   bits."  See also <bit>, <hidden flag>.

<flag day> n. A software change which is neither forward nor backward
   compatible, and which is costly to make and costly to revert.
   "Can we install that without causing a flag day for all users?"
   This term has nothing to do with the use of the word <flag> to mean
   a variable that has two values.  It came into use when a massive
   change was made to the <Multics> timesharing system to convert from
   the old ASCII code to the new one; this was scheduled for Flag Day,
   June 14, 1966.

<flaky> adj. (var sp. `flakey') Subject to frequent lossages.  See
   <lossage>.  This use is of course related to the common slang use
   of the word, to describe a person as eccentric or crazy.  A system
   that is flaky is working, sort of, enough that you are tempted to
   try to use it, but it fails frequently enough that the odds in
   favor of finishing what you start are low.  Commonwealth hackish
   prefers <dodgy>.

<flamage> /flay'm@j/ n. High-noise, low-signal postings to <USENET>
   or other electronic fora.  Often in the phrase "the usual

<flame> 1. vi. To speak incessantly and/or rabidly on some relatively
   uninteresting subject or with a patently ridiculous attitude.  When
   a discussion degenerates into useless controversy, one might tell
   the participants, "Now you're just flaming" or "Stop all that
   flamage!"  to try to get them to cool down (so to speak).  2.  To
   post an email message intended to insult and provoke.  <FLAME ON>:
   vi.  To continue to flame.  See <rave>, <burble>.  The punning
   reference to Marvel comics's Human Torch has been lost as recent
   usage completes the circle: "Flame on" now usually means
   "beginning of flame".

   A USENETter who was at WPI from 1972 to 1976 adds: I am 99% certain
   that the use of "flame" originated at WPI.  Those who made a
   nuisance of themselves insisting that they needed to use a TTY for
   "real work" came to be known as "flaming asshole lusers".
   Other, particularly annoying people became "flaming asshole
   ravers", which shortened to "flaming ravers", and ultimately
   "flamers".  I remember someone picking up on the Human Torch pun,
   but I don't think "flame on/off" was ever much used at WPI.  See
   also <asbestos cork award>.

<flame bait> n. A posting intended to trigger a <flame war>, or one
   which invites flames in reply.

<flame war> n. Acrimonious dispute, especially when conducted on a
   public electronic forum such as <USENET>.  Often merged to one
   word, <flamewar>.

<flamer> n. One who habitually flames others.  Said esp. of obnoxious
   <USENET> personalities.

<flap> vt. 1. To unload a DECtape (so it goes flap, flap, flap...).
   Old hackers at MIT tell of the days when the disk was device 0 and
   microtapes were 1, 2,... and attempting to flap device 0 would
   instead start a motor banging inside a cabinet near the disk!  2.
   By extension, to unload any magnetic tape.  See <microtape>,
   <macrotape>.  Modern cartridge tapes no longer actually flap, but
   the usage has remained.

<flat-ASCII> adj. Said of a text file wich contains only 7-bit ASCII
   characters and uses only ASCII-standard control characters (that
   is, has no embedded codes specific to a particular text formatter
   or markup language, and no <META>-characters.  Syn. <plain-ASCII>.

<flatten> v. To remove structural information, esp. to filter
   something with an implicit tree structure into a simple sequence of
   leaves.  "This code flattens an expression with parentheses into
   an equivalent <canonical> form."

<flavor> n. 1. Variety, type, kind.  "DDT commands come in two
   flavors."  "These lights come in two flavors, big red ones and
   small green ones."  See <vanilla>.  2. The attribute that causes
   something to be <flavorful>.  Usually used in the phrase "yields
   additional flavor."  "This convention yields additional flavor by
   allowing one to print text either right-side-up or upside-down."
   See <vanilla>.  This usage is almost certainly influenced by
   accepted terminology in particle physics, in which quarks (the
   constituents of e.g. protons) come in six flavors (up, down,
   strange, charm, top, bottom) and three colors (red, blue, green)
   --- however, its use at MIT almost certainly predated quark theory.

<flavorful> adj. Aesthetically pleasing.  See <random> and <losing>
   for antonyms.  See also the entries for <taste> and <elegant>.

<flippy> /flip'ee/ n. A single-side floppy disk altered for
   double-sided use by addition of a second write-notch, so called
   because it must be flipped over for the second side to be
   accessible.  No longer common.

<flush> v. 1. To delete something, usually superfluous.  "All that
   nonsense has been flushed."  Standard ITS terminology for aborting
   an output operation (but note sense 4 below!); one speaks of the
   text that would have been printed, but was not, as having been
   flushed.  Under ITS, if you asked to have a file printed on your
   terminal, it was printed a page at a time; at the end of each page,
   it asked whether you want to see more, and if you said no, it
   replied "FLUSHED".  (It is speculated that this term arose from a
   vivid image of flushing unwanted characters by hosing down the
   internal output buffer, washing the characters away before they can
   be printed.)  2. To leave at the end of a day's work (as opposed to
   leaving for a meal).  "I'm going to flush now."  "Time to
   flush."  3. To exclude someone from an activity, or to ignore a
   person.  4.  [UNIX/C] To force buffered I/O to disk, as with an
   `fflush(3)' call.  This is *not* an abort as in sense 1 but a
   demand for early completion!  UNIX hackers find the ITS usage
   confusing and vice versa.

<flytrap> n. See <firewall machine>.

<FOAF> [USENET] n.  Written-only acronym for Friend Of A Friend.  The
   source of an unverified, possibly untrue story.  This was not
   originated by hackers (it is used in Jan Brundvent's books on urban
   folklore) but is much better recognized on USENET and elsewhere
   than in the mainstream.

<foo> /foo/ 1. interj. Term of disgust.  2. Name used for temporary
   programs, or samples of three-letter names.  Other similar words
   are <bar>, <baz> (Stanford corruption of <bar>), and rarely RAG.
   3. Used very generally as a sample name for absolutely anything.
   4. First on the standard list of metasyntactic variables used in
   syntax examples.  See also: <bar>, <baz>, <qux>, <quux>, <QUUUX>,
   <corge>, <grault>, <garply>, <waldo>, <fred>, <plugh>, <xyzzy>.
   <moby foo>: See <moby>.

   <foo> is the <canonical> example of a `metasyntactic variable'; a
   name used in examples and understood to stand for whatever thing is
   under discussion, or any random member of a class of things under
   discussion.  To avoid confusion, hackers never use `foo' or other
   words like it as permanent names for anything.

   The etymology of hackish "foo" is obscure.  When used in
   connection with "bar" it is generally traced to the WWII-era army
   slang acronym FUBAR (Fucked Up Beyond All Recognition), later
   expurgated to <foobar> and then truncated.

   However, the use of the word "foo" itself has more complicated
   antecedents, including a long history in comic strips and cartoons.
   The old `Smokey Stover' comic strips by Bill Holman often
   included the word "FOO", in particular on license plates of cars;
   allegedly, "FOO" and "BAR" also occurred in Walt Kelly's
   `Pogo' strips.  In a 1938 cartoon Daffy Duck holds up a sign
   saying "SILENCE IS FOO!".  It is even possible that hacker usage
   actually springs from the title `FOO, Lampoons and Parody' of
   a comic book first issued 20 years later, in September 1958; the
   byline read "C.  Crumb" but this may well have been a sort-of
   pseudonym for noted weird-comix artist Robert Crumb.  The title FOO
   was featured in large letters on the front cover.

   Very probably hackish "foo" had no single origin and derives
   through all these channels from Yiddish "feh", or English

<foobar> n. Another common metasyntactic variable; see <foo>.

<fool> n. As used by hackers, specifically describes a person who
   habitually reasons from obviously or demonstrably incorrect
   premises and cannot be persuaded to do otherwise by evidence; it is
   not generally used in its other senses, i.e. to describe a person
   with a native incapacity to reason correctly, or a clown.  Indeed,
   in hackish experience many fools are capable of reasoning all too
   effectively in executing their errors.  See also <cretin>, <loser>.

<footprint> n. 1. The floor or desk area taken up by a piece of
   hardware. 2. [IBM] The audit trail (if any) left by a crashed
   program (often in plural, `footprints').

<for the rest of us> [Mac slogan] adj. Used to describe a <spiffy>
   product whose affordability shames other comparable products, or
   (more often) used sarcastically to describe <spiffy>, but very
   overpriced products.

<foreground> [UNIX] adj.,vt. On a time-sharing system, a task
   executing in foreground is one able to accept input from and return
   output to the user; oppose <background>.  Normally, there is only
   one foreground task per terminal (or terminal window); having
   multiple processes simultaneously reading the keyboard is a good
   way to <lose>.  By extension, "to foreground" a task is to bring
   it to the top of one's <stack> for immediate processing, and in
   this sense hackers often use it for non-computer tasks.

<forked> [UNIX] adj. Terminally slow, or dead.  Originated when the
   system slowed to incredibly bad speeds due to a process recursively
   spawning copies of itself (using the Unix system call `fork(2)')
   and taking up all the process table entries.

<fortune cookie> [UNIX] n. A random quote, item of trivia, joke or
   maxim printed to the user's tty at login time or (less commonly) at
   logout time.  Items from this jargon file have often been used as
   fortune cookies.

<fossil> n. 1. In software, a misfeature that becomes understandable
   only in historical context, as a remnant of times past retained so
   as not to break compatibility.  Example: the retention of octal as
   default base for string escapes in C in spite of the better match
   of hexadecimal to modern byte-addressable architectures.  See
   <dusty deck>. 2. More restrictively, a feature with past but no
   present utility.  Example: the force-all-caps (LCASE) bits in the
   V7 and <BSD UNIX> tty driver, designed for use with monocase
   terminals.  In a perversion of the usual backwards compatibility
   goal, this functionality has actually been expanded and renamed in
   some later <USG UNIX> releases as the IUCLC and OLCUC bits.

<fred> n. The personal name most frequently used as a metasyntactic
   variable (see <foo>).  Allegedly popular because it's easy to type
   on a standard QWERTY keyboard.  It is alternatively alleged to be
   an acronym for "Flipping Ridiculous Electronic Device" (other
   f-verbs may be substituted for "flipping")

<freeware> n. Free software, often written by enthusiasts and usually
   distributed by electronic mail, local bulletin boards, <USENET>, or
   other electronic media.  See <shareware>.

<fried> adj. 1. Non-working due to hardware failure; burnt out.
   Especially used of hardware brought down by a power glitch, short,
   or other electrical event.  (Sometimes this literally happens to
   electronic circuits!  In particular, resistors can burn out and
   transformers can melt down, emitting terribly-smelling smoke.
   However, this term is also used metaphorically.)  2. Of people,
   exhausted.  Said particularly of those who continue to work in such
   a state.  Often used as an explanation or excuse.  "Yeah, I know
   that fix destroyed the file system, but I was fried when I put it

<frob> /frob/ 1. n. [MIT] The official Tech Model Railroad Club
   definition was "FROB = protruding arm or trunnion", and by
   metaphoric extension any somewhat small thing; an object that you
   can comfortably hold in one hand; something you can frob.  See
   <frobnitz>.  2. v. Abbreviated form of <frobnicate>.  3. [from the
   <MUD> world] To request <wizard> privileges on the `professional
   courtesy' grounds that one one is a wizard elsewhere.

<frobnicate> /frob'ni-kayt/ vt. To manipulate or adjust, to tweak.
   Thus: "Please frob the light switch."  (That is, flip the light
   switch.), but also "Stop frobbing that clasp; you'll break it."
   Poss. derived from <frobnitz>.  Usually abbreviated to <frob>, but
   <frobnicate> is recognized as the official full form.  Thus one has
   the saying "to frob a frob".  See <tweak> and <twiddle>.  Usage:
   <frob>, <twiddle>, and <tweak> sometimes connote points along a
   continuum.  <frob> connotes aimless manipulation; <twiddle>
   connotes gross manipulation, often a coarse search for a proper
   setting; <tweak> connotes fine-tuning.  If someone is turning a
   knob on an oscilloscope, then if he's carefully adjusting it he is
   probably tweaking it; if he is just turning it but looking at the
   screen he is probably twiddling it; but if he's just doing it
   because turning a knob is fun, he's frobbing it.  The variant
   "frobnosticate" has been recently reported.

<frobnitz> /frob'nits/, pl. <frobnitzem> (frob'nitsm) n. An unspecified
   physical object, a widget.  Also refers to electronic black boxes.
   This rare form is usually abbreviated to FROTZ, or more commonly to
   <frob>.  Also used are "frobnule" and "frobule".  Starting
   perhaps in 1979, "frobozz" (fruh-bahz'), plural "frobbotzim"
   (fruh-bot'z@m) has also become very popular, largely due to its
   exposure as a name via <Zork>.  These can also be applied to
   nonphysical objects, such as data structures.

<frog> alt. `phrog' 1. interj. Term of disgust (we seem to have a lot
   of them).  2. Used as a name for just about anything.  See <foo>.
   3.  n.  Of things, a crock.  Of people, somewhere inbetween a
   turkey and a toad.  4. <froggy>: adj. Similar to <bagbiting>, but
   milder.  "This froggy program is taking forever to run!"

<front end> n. 1. A subsidiary computer that doesn't do much. 2. What
   you're talking to when you have a conversation with someone who is
   making replies without paying attention. "Look at the dancing
   elephants!"  "Uh-huh" "Do you know what I just said?"
   "Sorry, you were talking to the front end".

<frotz> /frotz/ 1. n. See <frobnitz>.  2. <mumble frotz>: An
   interjection of very mild disgust.

<frotzed> /frotzt/ adj. <down> due to hardware problems.

<fry> 1. vi. To fail.  Said especially of smoke-producing hardware
   failures.  More generally, to become non-working.  Usage: never
   said of software, only of hardware and humans.  See <fried>, <magic
   smoke>. 2. vt. To cause to fail; to <roach>, <toast> or <hose> a
   piece of hardware (never used of software or humans).

<FTP> /ef-tee-pee/, *not* /fit'ip/ 1. n. The File Transfer
   Protocol for transmitting files between systems on the Internet.
   2.  vt. To transfer a file using the File Transfer Protocol. 3.
   Sometimes used as a generic even for file transfers not using
   <FTP>. "Lemme get this copy of Wuthering Heights FTP'd from

<fuck me harder> excl. Sometimes uttered in response to egregious
   misbehavior, esp. in software, and esp. of those which seem
   unfairly persistent (as though designed in by the imp of the
   perverse).  Often theatrically elaborated: "Aiighhh! Fuck me with
   a piledriver and sixteen feet of curare-tipped wrought-iron fence
   *and no lubricants!*"  The phrase is sometimes heard
   abbreviated FMH in polite company.

<FUD wars> /fud worz/ n. [from `Fear, Uncertainty and Doubt']
   Political posturing engaged in by hardware and software vendors
   ostensibly committed to standardization but actually willing to
   fragment the market to protect their own share.  The OSF vs. UNIX
   International conflict, for example.

<fudge> 1. v. To perform in an incomplete but marginally acceptable
   way, particularly with respect to the writing of a program.  "I
   didn't feel like going through that pain and suffering, so I fudged
   it."  2. n. The resulting code.

<fudge factor> n. A value or parameter that is varied in an ad hoc way
   to produce the desired result.  The terms "tolerance" and
   "slop" are also used, though these usually indicate a one-sided
   leeway, such as a buffer which is made larger than necessary
   because one isn't sure exactly how large it needs to be, and it is
   better to waste a little space than to lose completely for not
   having enough.  A fudge factor, on the other hand, can often be
   tweaked in more than one direction.  A good example is the <fuzz>
   typically needed in floating-point calculations: two numbers being
   compared for equality must be allowed to differ by a small amount;
   if that amount is too small, a computation may never terminate,
   while if it is too large, results will be needlessly inaccurate.
   Fudge factors are frequently adjusted incorrectly by programmers
   who don't fully understand their import.

<fuel up> vi. To eat or drink hurriedly in order to get back to
   hacking.  "Food-p?" "Yeah, let's fuel up." "Time for a
   <great-wall>!".  See also <ORIENTAL FOOD>.

<fuggly> /fuhg'lee/ adj. Emphatic form of <funky>; funky + ugly (or
   possibly a contraction of "fuckin' ugly"). Unusually for hacker
   slang, this may actually derive from black street-jive.  To say it
   properly, the first syllable should be growled rather than spoken.
   Usage: humorous.  "Man, the ASCII-to-EBCDIC code in that printer
   driver is *fuggly*."  See also <wonky>.

<funky> adj. Said of something which functions, but in a slightly
   strange, klugey way.  It does the job and would be difficult to
   change, so its obvious non-optimality is left alone.  Often used to
   describe interfaces.  The more bugs something has that nobody has
   bothered to fix because workarounds are easier, the funkier it is.
   <TECO> and UUCP are funky.  The Intel i860's exception handling is
   extraordinarily funky.  Most standards acquire funkiness as they
   age.  "The new mailer is installed, but is still somewhat funky;
   if it bounces your mail for no reason, try resubmitting it."
   "This UART is pretty funky.  The data ready line is active-high in
   interrupt mode, and active-low in DMA mode."  See <fuggly>.

<funny money> n. (also `play money') 1. Notional `dollar' units of
   computing time and/or storage handed to students at the beginning
   of a computer course by professors; also called "purple money"
   (in implicit opposition to real or "green" money). When your
   funny money ran out, your account froze and you needed to go to a
   professor to get more.  Formerly a common practice, this has now
   been made sufficiently rare by the plunging cost of timesharing
   cycles that it has become folklore.  The amounts allocated were
   almost invariably too small, even for the non-hackers who wanted to
   slide by with minimum work.  In extreme cases the practice led to
   small-scale black markets in bootlegged computer accounts. 2. By
   extension, phantom money or quantity tickets of any kind used as a
   resource-allocation hack within a system.

<fuzz> n. In floating-point arithmetic, the maximum difference allowed
   between two quantities for them to compare equal.  Has to be set
   properly relative to the FPU's precision limits.  See <fudge

<fuzzball> [TCP/IP hackers] n. A DEC LSI-11 running a particular suite
   of homebrewed software by Dave Mills and assorted co-conspirators,
   used in the early 80's for Internet protocol testbedding and
   experimentation.  These were used as NSFnet backbone sites in its
   early 56KB-line days; a few of these are still active on the
   Internet as of early 1990, doing odd jobs such as network time

                                {= G =}

<gabriel> /gay'bree-@l/ [for Dick Gabriel, SAIL volleyball fanatic]
   n.  An unnecessary (in the opinion of the opponent) stalling
   tactic, e.g., tying one's shoelaces or hair repeatedly, asking the
   time, etc.  Also used to refer to the perpetrator of such tactics.
   Also, "pulling a Gabriel", "Gabriel mode".

<gag> vi. Equivalent to <choke>, but connotes more disgust. "Hey,
   this is Fortran code.  No wonder the C compiler gagged."  See also

<gang bang> n. The use of large numbers of loosely-coupled programmers
   in an attempt to wedge a great many features into a product in a
   short time.  While there have been memorable gang bangs (ref: that
   over-the-weekend assembler port mentioned in Steven Levy's
   "Hackers"), most are perpetrated by large companies trying to
   meet deadlines and produce enormous buggy masses of code entirely
   lacking in orthogonality (see <orthogonal>).  When market-driven
   managers make a list of all the features the competition have and
   assign one programmer to implement each, they often miss the
   importance of maintaining strong invariants, like relational

<garbage collect> vi., (also "garbage collection", n.) See <GC>.

<garply> /gar'plee/ n. [Stanford] Another meta-syntactic variable (see
   <foo>) popular among SAIL hackers.

<gas> [as in "gas chamber"] interj. 1. A term of disgust and hatred,
   implying that gas should be dispensed in generous quantities,
   thereby exterminating the source of irritation.  "Some loser just
   reloaded the system for no reason!  Gas!"  2. A term suggesting
   that someone or something ought to be flushed out of mercy.  "The
   system's wedging every few minutes.  Gas!"  3. vt.  <flush>.
   "You should gas that old crufty software."  4.  GASEOUS adj.
   Deserving of being gassed.  Usage: primarily used by Geoff
   Goodfellow at SRI, but spreading; became particularly popular after
   the Moscone/Milk murders in San Francisco, when it was learned that
   Dan White (who supported Proposition 7) would get the gas chamber
   under 7 if convicted.  He was eventually found not guilty by reason
   of insanity.

<GC> /jee-see/ [from LISP terminology; "Garbage Collect"] 1. vt. To
   clean up and throw away useless things.  "I think I'll <GC> the
   top of my desk today."  When said of files, this is equivalent to
   <GFR>.  2.  vt. To recycle, reclaim, or put to another use.  3. n.
   An instantiation of the garbage collector process. `Garbage
   collection' is computer science jargon for a particular class of
   strategies for dynamically reallocating computer memory.  One such
   strategy involves periodically scanning all the data in memory and
   determining what is no longer useful; useless data items are then
   discarded so that the memory they occupy can be recycled and used
   for another purpose.  Implementations of the LISP language usually
   use garbage collection.  In slang, the full phrase is sometimes
   heard but the acronym is more frequently used because it's shorter.
   Note that there is an ambiguity in usage that has to be resolved by
   context: "I'm going to garbage-collect my desk" usually means to
   clean out the drawers, but it could also mean to throw away or
   recycle the desk itself.

   Warning: in X programming, a "GC" may be a graphics context.  This
   technical term has nothing to do with the jargon <GC>!

<GCOS> n. A quick and dirty <clone> of System/360 DOS that emerged
   from GE about 1970; originally called GECOS (the General Electric
   Comprehensive Operating System) and later kluged to support
   primitive timesharing and transaction processing.  After the buyout
   of GE's computer division by Honeywell the name was changed to
   General Comprehensive Operating System (GCOS). Other OS groups at
   Honeywell began referring to it as `God's Chosen Operating System',
   allegedly in reaction to the GCOS crowd's uninformed and snotty
   attitude about the superiority of their product.  All this might be
   of zero interest, except for two facts: 1) the GCOS people won the
   political war, resulting in the orphaning and eventual death of
   Honeywell <Multics>, and 2) GECOS/GCOS left one permanent mark
   on UNIX.  Some early UNIX systems at Bell Labs were used as front
   ends to GCOS machines; the field added to /etc/passwd to carry GCOS
   ID information was called `the GECOS field' and survives today as
   the pw_gecos member used for the user's full name and other
   human-id information.  GCOS itself played a major rule in keeping
   Honeywell a dismal also-ran in the mainframe market, and was itself
   ditched for UNIX in the late 1980s when Honeywell retired its aging
   <big iron> designs.


<gedanken> /g@-dahn'kn/ adj. Wild-eyed; impractical; not
   well-thought-out; untried; untested.  "Gedanken" is a German word
   for "thought".  A thought experiment is one you carry out in your
   head.  In physics, the term "gedanken experiment" is used to
   refer to an experiment that is impractical to carry out, but useful
   to consider because you can reason about it theoretically.  (A
   classic gedanken experiment of relativity theory involves thinking
   about a man flying through space in an elevator.)  Gedanken
   experiments are very useful in physics, but you have to be careful.
   It was a gedanken experiment that led Aristotle to conclude that
   heavy things always fall faster than light things (he thought about
   a rock and a feather); this was accepted until Galileo proved
   otherwise.  Among hackers, however, the word has a pejorative
   connotation.  It is said of a project, especially one in artificial
   intelligence research, which is written up in grand detail
   (typically as a Ph.D. thesis) without ever being implemented to any
   great extent.  Such a project is usually perpetrated by people who
   aren't very good hackers or find programming distasteful or are
   just in a hurry.  A gedanken thesis is usually marked by an obvious
   lack of intuition about what is programmable and what is not, and
   about what does and does not constitute a clear specification an

<geek out> vi. To temporarily enter techno-nerd mode while in a
   non-hackish context, for example at parties held near computer
   equipment.  Especially used when you need to do something highly
   technical and don't have time to explain: "Pardon me while I geek
   out for a moment."

<gender mender> n. (also "gender bender" and "sex changer") A
   cable connector shell with either two male or two female connectors
   on it, used to correct the mismatches that result when some <loser>
   didn't understand the RS232C specification and the distinction
   between DTE and DCE.  Used esp. for RS-232C parts in either the
   original D-25 or the IBM PC's bogus D-9 format.

<General Public Virus> n. Pejorative name for some versions of the
   <GNU> project <copyleft> or General Public License, which requires
   that any tools or <app>s incorporating copylefted code must be
   source-distributed on the same counter-commercial terms as GNU
   stuff.  Thus it is alleged that the copyleft `infects' software
   generated with GNU tools, which may in turn infect other software
   that reuses any of its code.  FSF's official position as of January
   1991 is that only "programs textually incorporating significant
   amounts of GNU code" fall under the GPL and that the infection is
   not passed on to third parties unless actual GNU source is
   transmitted (as in, for example, use of the Bison parser skeleton).
   Nevertheless, widespread suspicion that the <copyleft> language is
   `boobytrapped' has caused many developers to avoid using GNU tools
   and the <GPL> license.

<generate> vt. To produce something according to an algorithm or
   program or set of rules, or as a (possibly unintended) side effect
   of the execution of an algorithm or program.  The opposite of
   <parse>.  This term retains its mechanistic connotations (though
   often humorously) when used of human behavior.  "The guy is
   rational most of the time, but mention nuclear energy around him
   and he'll generate <infinite> flamage."

<Get a life!> imp. Hacker-standard way of suggesting that the person
   to whom you are speaking has succumbed to terminal geekdom (see
   <computer geek>).  Often heard on <USENET>.  This exhortation was
   originally uttered by William Shatner on a Saturday Night Live
   episode in a speech which ended "Get a *life*!".

<Get a real computer!> imp. Typical hacker response to news that
   somebody is having trouble getting work done on a system that is a)
   single-tasking, b) has no Winchester, or c) has an address space
   smaller than 4 megabytes.  This is as of 1990; note that the
   threshold for `real computer' rises with time, and it may well be
   (for example) that machines with character-only displays will be
   considered `unreal' in a few years.  See <bitty box> and <toy>.

<GFR> /jee eff ar/ vt. [acronym, ITS] From "Grim File Reaper", an
   ITS utility.  To remove a file or files according to some
   program-automated or semi-automatic manual procedure, especially
   one designed to reclaim mass storage space or reduce namespace
   clutter.  Often generalized to pieces of data below file level.
   "I used to have his phone number but I guess I <GFR>ed it."  See
   also <prowler>, <reaper>.

<gig> /jig/, rarely /gig/ n. Short for "gigabyte" (1024 megabytes);
   esp. used in describing amounts of <core> or mass storage. "My
   machine just got upgraded to a quarter-gig".  See also <kilo>.

<giga-> /ji'ga/ pref. See <kilo>.

<GIGO> /gie'goh/ [acronym] 1. Garbage In, Garbage out -- Usually said
   in response to lusers who complain that a program didn't complain
   about faulty data.  Also commonly used to describe failures in
   human decision making due to faulty, incomplete or imprecise data.
   2. Garbage In, Gospel Out -- this more recent expansion is a
   sardonic comment on the tendency human beings have to put excessive
   trust in "computerized" data.

<gillion> /jill'yun/ n. 10^9.  [From giga, following construction of
   mega/million and notional tera/trillion] Same as an American
   billion or a British `milliard'.

<glark> /glark/ vt. To figure something out from context. "The System
   III manuals are pretty poor, but you can generally glark the
   meaning from context".  Interestingly, the original sentence was
   "This gubblick contains many nonsklarkish English flutzpahs, but
   the overall pluggandisp can be glorked [sic] from context." by
   David Moser, quoted by Douglas Hofstadter in his `Metamagical
   Themas' column in the January 1981 Scientific American.  It is
   conjectured that hackish usage mutated the verb to `glark' because
   <glork> was already an established jargon term.

<glass> [IBM] n. Synonym for <silicon>.

<glass tty> /glas tee-tee-wie/ or /glas ti-tee/ n. A terminal which
   has a display screen but which, because of hardware or software
   limitations, behaves like a teletype or other printing terminal ,
   thereby combining the disadvantages of both: like a printing
   terminal, it can't do fancy display hacks, and like a display
   terminal, it doesn't produce hard copy An example is Lear-Siegler
   the ADM-3 (without cursor control).  See <tube>, <tty>.  See
   Appendix A for an interesting true story about glass TTYs.

<glitch> /glich/ [from German "glitchen" to slip, via Yiddish
   "glitshen", to slide or skid] 1. n. A sudden interruption in
   electric service, sanity,, continuity, or program function.
   Sometimes recoverable.  An interruption in electric service is
   specifically called a "power glitch".  This is of grave concern
   because it usually crashes all the computers.  More common in
   slang, though, a hacker who got to the middle of a sentence and
   then forgotten how he or she intended to complete it might say,
   "Sorry, I just glitched".  2. vi. To commit a glitch.  See
   <gritch>.  3. vt.  [Stanford] To scroll a display screen several
   lines at a time.  This derives from some oddities in the terminal
   behavior under the mutant TOPS-10 formerly used at SAIL. 4.  (obs.)
   Same as <magic cookie>, sense #2.

<glob> /glob/, *not* /glohb/ [UNIX, from "glob", the name of a
   subprogram that translated wildcards in archaic Bourne Shell
   versions] v. To expand special characters in a wildcarded name (the
   action is "globbing").  The UNIX conventions for filename
   wildcarding have become sufficiently pervasive that many hackers
   use some of them in written English, especially in email or news on
   technical topics.  Those commonly encountered include:

     *    wildcard for any string (see UN*X).
     ?    wildcard for any character (generally only read this way
          at the beginning or in the middle of a word).
     []   wildcard matching one character from a specified set.
     {}   alternation of comma-separated alternatives.  Thus,
          `{foo,bar}baz' would be read as `foobar' or `foobaz'.

   Some examples: "He said his name was [KC]arl" (expresses
   ambiguity).  "That got posted to talk.politics.*" (all the
   talk.politics subgroups on <USENET>).  Other examples are given
   under the entry for `X'.  <glob> as a noun refers to the act of
   expanding a string using these conventions.  It is also used as a

<glork> /glork/ 1. interj. Term of mild surprise, usually tinged with
   outrage, as when one attempts to save the results of two hours of
   editing and finds that the system has just crashed.  2. Used as a
   name for just about anything.  See <foo>.  3. vt. Similar to
   <glitch>, but usually used reflexively.  "My program just glorked

<gnarly> adj. Both <obscure> and <hairy> in the sense of complex.
   "Yeech --- the tuned assembler implementation of BitBlt is really
   gnarly!"  From a similar but less specific usage in surfer slang.

<GNU> /gnoo/, *not* /noo/ 1. [acronym for "GNU's Not UNIX!"] A
   UNIX-workalike development effort of the Free Software Foundation
   headed by Richard Stallman (  GNU EMACS and
   the GNU C compiler, two tools designed for this project, have
   become very popular in hackerdom.  See <EMACS>, <copyleft>,
   <General Public Virus>.  2. Noted UNIX hacker John Gilmore
   (, ironically enough one of the best-known and
   most vocal opponents of the "information should not be property"
   philosophy behind GNU (sense #1).

<GNUMACS> /gnoo'maks/ [contraction of "Gnu Emacs"] Often-heard
   abbreviated name for the <GNU> project's flagship tool, <EMACS>.
   Used esp. in contrast with <GOSMACS>.

<go flatline> [from cyberpunk SF, refers to flattening of EEG traces
   upon brain-death] vi., also adjectival <flatlined>. 1. To die,
   terminate, or fail, esp. irreversibly.  In hacker parlance this is
   used of machines only, human death being considered somewhat too
   serious a matter to employ jargon-jokes about. 2. To go completely
   quiescent; said of machines undergoing controlled shutdown. "You
   can suffer file damage if you shut down UNIX but power off before
   the system has gone flatline." 3. A particular failure mode of
   video tubes in which vertical scan is lost, so all one sees is a
   bright horizontal line bisecting the screen.

<gobble> vt. To consume or to obtain.  The phrase <gobble up> tends to
   imply "consume", while <gobble down> tends to imply "obtain".
   "The output spy gobbles characters out of a <tty> output buffer."
   "I guess I'll gobble down a copy of the documentation tomorrow."
   See also <snarf>.

<gonk> /gonk/ vt.,n. 1. To prevaricate or to embellish the truth
   beyond any reasonable recognition.  In German the term is
   (fictively) "gonken", in spanish the verb becomes "gonkar".
   "You're gonking me.  That story you just told me is a bunch of
   gonk."  In German, "Du Gonkst mir"  (You're pulling my leg).
   See also <gonkulator>.  2. [British] To grab some sleep at an odd

<gonkulator> /gon'kyoo-lay-tr/ [from the old "Hogan's Heroes" TV
   series] n. A pretentious piece of equipment that actually serves no
   useful purpose.  Usually used to describe one's least favorite
   piece of computer hardware.  See <gonk>.

<gonzo> /gon'zo/ [from Hunter S. Thompson] adj. Overwhelming;
   outrageous; over the top; very large, esp.  used of collections of
   source code, source files or individual functions.  Has some of the
   connotations of <moby> and <hairy>, q.v.

<Good Thing> adj. Often capitalized; always pronounced as if
   capitalized.  1. Self-evidently wonderful to anyone in a position
   to notice: "The Trailblazer's 19.2Kbaud PEP mode with on-the-fly
   Lempel-Ziv compression is a Good Thing for sites relaying
   netnews." 2. Something which can't possibly have any ill side
   effects and may save considerable grief later: "Removing the
   self-modifying code from that shared library would be a Good
   Thing." 3. When said of software tools or libraries, as in "YACC
   is a Good Thing", specifically connotes that the thing has
   drastically reduced a programmer's work load.  Oppose <Bad Thing>.

<gorilla arm> n. The side-effect that destroyed touch-screens as a
   mainstream input technology despite a promising start in the early
   eighties.  It seems the designers of all those <spiffy> touch-menu
   systems failed to notice that humans aren't designed to hold their
   arms in front of their faces making small motions.  After more than
   a very few selects the arm begins to feel sore, cramped, and
   oversized, hence "gorilla arm".  This is now considered a classic
   Horrible Example and cautionary tale to human-factors designers;
   "remember the gorilla arm" is shorthand for "how's this gonna
   fly in *real* use?"

<gorp> /gorp/ [CMU, perhaps from a brand of dried hiker's food?]
   Another metasyntactic variable, like <foo> and <bar>.

<GOSMACS> /goz'maks/ [contraction of "Gosling Emacs"] n. The first
   <EMACS>-in-C implementation, predating but now largely eclipsed by
   <GNUMACS>.  Originally freeware; a commercial version is now
   modestly popular as "UniPress Emacs".

<Gosperism> /goss'p@r'iz'm/ A hack, invention, or saying by
   arch-hacker R. William (Bill) Gosper.  This notion merits its own
   term because there are so many of them.  Many of the entries in
   <HAKMEM> are Gosperisms; see also <life>.

<grault> /grawlt/ n. Yet another meta-syntactic variable, invented by
   Mike Gallaher and propagated by the <GOSMACS> documentation.  See

<gray goo> n. A hypothetical substance composed of <sagans> of
   sub-micron-sized Von Neumann machines (self-replicating robots)
   programmed to make copies of themselves out of whatever is
   available.  The image that goes with the term is one of the entire
   biosphere of Earth being eventually converted to robot goo.  This
   is the simplest of the <nanotechnology> disaster scenarios and is
   easily refuted by arguments from energy requirements and elemental

<Great Renaming> n. The <flag day> on which all of the groups on the
   <USENET> had their names changed from the net.* format to the
   current multiple-hierarchies scheme.

<great-wall> [from SF fandom] vi.,n. A mass expedition to an oriental
   restaurant, esp. one where food is seved family-style and shared.
   There is a common heuristic about the amount of food to order
   expressed as "For N people, get N - 1 entrees.".  See <ORIENTAL
   FOOD>, <ravs>, <stir-fried random>.

<Green Book> n. 1. One of the three standard PostScript references
   (`PostScript Language Program Design', Adobe Systems,
   Addison-Wesley 1988 QA76.73.P67P66 ISBN 0-201-14396-8); see also
   <Red Book>, <Blue Book>).  2. `Smalltalk-80: Bits of History,
   Words of Advice', Glenn Krasner, Addison-Wesley 1983,
   QA76.8.S635S58, ISBN 0-201-11669-3 (this is also associated with
   blue and red books).  3. The `X/Open Compatibility Guide'.  Defines
   an international standard <UNIX> environment that is a proper
   superset of POSIX/SVID; also includes descriptions of a standard
   utility toolkit, systems administrations features, and the like.
   This grimoire is taken with particular seriousness in Europe.  See
   <Purple Book>.  4. The IEEE 1003.1 POSIX Operating Systems
   Interface standard has been dubbed "The Ugly Green Book".  5. Any
   of the 1992 standards which will be issued by the CCIT 10th plenary
   assembly.  Until now, hese have changed color each review cycle
   (1984 was <Red Book>, 1988 <Blue Book>); however, it is rumored
   that this convention is going to be dropped befor 1992.  These
   include, among other things, the X.400 email spec and the Group 1
   through 4 fax standards.  See also <Blue Book>, <Red Book>, <Green
   Book>, <Silver Book>, <Purple Book>, <Orange Book>, <White Book>,
   <Dragon Book>, <Pink-Shirt Book>.

<green bytes> n. 1. Meta-information imbedded in a file such as the
   length of the file or its name; as opposed to keeping such
   information in a separate description file or record.  Name comes
   from an IBM user's group meeting where these two approaches were
   being debated and the diagram of the file on the blackboard had the
   "green bytes" drawn in green.  2. By extension, the
   non-data bits in any self-describing format.  "A GIF file
   contains, among other things, green bytes describing the packing
   method for the image."

<green lightning> [IBM] n. Apparently random flashing streaks on the
   face of 3278-9 terminals while a programmable symbol set is being
   loaded.  This hardware bug was left deliberately unfixed, as some
   bright spark suggested that this would let the user know that
   `something is happening'. It certainly does.  2. [proposed] Any bug
   perverted into an alleged feature by adroit rationalization or
   marketing.  E.g.  "Motorola calls the CISC cruft in the 8800
   architecture `compatibility logic', but I call it green

<GREP> /grep/ [from the qed/ed editor idiom g/re/p (Global search for
   Regular Expression and Print) via <UNIX> `grep(1)'] vt. To rapidly
   scan a file or file set looking for a particular string or pattern.
   By extension, to look for something by pattern. "Grep the bulletin
   board for the system backup schedule, would you?"

<grind> vt. 1. [MIT and Berkeley] To format code, especially LISP
   code, by indenting lines so that it looks pretty.  This usage was
   associated with the MACLISP community and is now rare;
   <prettyprint> was and is the generic term for such operations.  2.
   [UNIX] To generate the formatted version of a document from the
   nroff, troff, TeX or Scribe source. 3. To run seemingly
   interminably, performing some tedious and inherently useless task.
   Similar to <crunch>, <grovel>.  3. <grind grind> excl. Roughly,
   "Isn't the machine slow today!"

<grind crank> n. A mythical accessory to a terminal.  A crank on the
   side of a monitor, which when operated makes a zizzing noise and
   causes the computer to run faster.  Usually one does not refer to a
   grind crank out loud, but merely makes the appropriate gesture and
   noise.  See <grind>, and <wugga wugga>.

   Historical note: At least one real machine actually had a grind
   crank --- the R1, a research machine built towards the the end of
   the days of the great vacuum tube computers in 1959.  R1 (also
   known as "The Rice Institute Computer" - TRIC, and later as "The
   Rice University Computer" - TRUC) had a single step/free run
   switch for use when debugging programs.  Since single stepping
   through a large program was rather tedious, there was also a crank
   with a cam and gear arrangement that repeatedly pushed the single
   step button.  This allowed one to "crank" through a lot of code,
   then slow down to single step a bit when you got near the code of
   interest, poke at some registers using the "console typewriter",
   and then keep on cranking.

<gritch> /grich/ 1. n. A complaint (often caused by a <glitch>).  2.
   vi.  To complain.  Often verb-doubled: "Gritch gritch".  3.  A
   synonym for <glitch> (as verb or noun).

<grok> /grok/ [from the novel "Stranger in a Strange Land", by
   Robert Heinlein, where it is a Martian verb meaning literally "to
   drink" and metaphorically "to be one with"] vt. 1. To
   understand, usually in a global sense.  Connotes intimate and
   exhaustive knowledge.  Contrast <zen>, similar supernal
   understanding as a single brief flash.  2. Used of programs, may
   connote merely sufficient understanding, e.g., "Almost all C
   compilers grok void these days."

<gronk> /gronk/ [popularized by the cartoon strip "B.C." by Johnny
   Hart, but the word apparently predates that] vt. 1. To clear the
   state of a wedged device and restart it.  More severe than "to
   <frob>".  2. To break.  "The teletype scanner was gronked,
   so we took the system down."  3. <gronked>: adj. Of people, the
   condition of feeling very tired or sick.  Oppose <broken>, which
   means about the same as <gronk> used of hardware but connotes
   depression or mental/emotional problems in people.  4. <gronk out>:
   vi. To cease functioning.  Of people, to go home and go to sleep.
   "I guess I'll gronk out now; see you all tomorrow."

<grovel> vi. 1. To work interminably and without apparent progress.
   Often used transitively with "over" or "through". "The file
   scavenger has been grovelling through the file directories for ten
   minutes now."  Compare <grind> and <crunch>.  Emphatic form:
   <grovel obscenely>.  2. To examine minutely or in complete detail.
   "The compiler grovels over the entire source program before
   beginning to translate it."  "I grovelled through all the
   documentation, but I still couldn't find the command I wanted."

<grunge> [Cambridge] n. Code which is `dead' (can never be accessed)
   due to changes in other parts of the program.  The preferred term
   in North America is <dead code>,

<grungy> /gruhn'jee/ adj. Incredibly dirty, greasy, or grubby.
   Anything which has been washed within the last year is not really
   grungy.  Also used metaphorically; hence some programs (especially
   crocks) can be described as grungy.  Now (1990) also common in
   mainstream slang.

<gubbish> /guh'bish/ [a portmanteau of "garbage" and "rubbish"?]
   n.  Garbage; crap; nonsense.  "What is all this gubbish?"  The
   opposite portmanteau "rubbage" is also reported.

<guiltware> n. <freeware> decorated with a message telling one how
   long and hard the author worked on this program and intimating that
   one is a no-good freeloader if one does not immediately send the
   poor suffering martyr gobs of money.

<gumby> /guhm'bee/ [from a class of Monty Python characters, poss.
   themselves named after a '60s claymation character] n. An act of
   minor but conspicuous stupidity, often in <gumy maneuver> or <pull
   a gumby>.

<gun> [from the :GUN command on ITS] vt. To forcibly terminate a
   program or job (computer, not career).  "Some idiot left a
   background process running soaking up half the cycles, so I gunned
   it."  Compare <can>.

<gurfle> /ger'fl/ interj. An expression of shocked disbelief. "He
   said we have to recode this thing in FORTRAN by next week.
   Gurfle!"  Compare <weeble>.

<guru> n. 1. [UNIX] An expert.  Implies not only <wizard> skill but a
   history of being a knowledge resource for others.  Less often, used
   (with a qualifier) for other experts on other systems, as in "VMS
   guru".  2. Amiga equivalent of "panic" in UNIX. When the system
   crashes a cryptic message "GURU MEDITATION #XXXXXXXX.YYYYYYYY"
   appears, indicating what the problem was.  An Amiga guru can figure
   things out from the numbers.  Generally a <guru> event must be
   followed by a <vulcan nerve pinch>.

                                {= H =}

<h infix> [from SF fandom] A method of "marking" common words in the
   linguist's sense, i.e. calling attention to the fact that they are
   being used in a nonstandard, ironic or humorous way.  Orig. in the
   fannish catchphrase "Bheer is the One True Ghod" from decades
   ago.  H-infix marking of "Ghod" and other words spread into the
   Sixties counterculture via underground comix, and into early
   hackerdom either from the counterculture or SF fandom (all three
   overlapped heavily at the time). More recently, the h infix has
   become an expected feature of benchmark names, i.e.  Whetstone,
   Dhrystone, Rhealstone, etc; this is prob. patterning on the
   original Whetstone name but influenced by the
   fannish/counterculture H infix.

<ha ha only serious> [from SF fandom, orig. as mutation of HHOK, "Ha
   Ha Only Kidding"] A phrase that aptly captures the flavor of much
   hacker discourse (often seen abbreviated as HHOS). Applied
   especially to parodies, absurdities and ironic jokes that are both
   intended and perceived to contain a possibly disquieting amount of
   truth, or truths which are constructed on in-joke and self-parody.
   The jargon file contains many examples of ha-ha-only-serious in
   both form and content.  Indeed, the entirety of hacker culture is
   often perceived as ha-ha-only-serious by hackers themselves; to
   take it either too lightly or too seriously marks a person as an
   outsider or one in <larval stage>.  For further enlightenment on
   this subject, consult any Zen master.  See also <HUMOR, HACKER> and
   <AI koans>.

<hack> 1. n. Originally a quick job that produces what is needed, but
   not well.  2. n. An incredibly good, and perhaps very
   time-consuming, piece of work that produces exactly what is needed.
   3. The result of a hack (sense 1 or 2); 3. <neat hack>: A clever
   technique.  Also, a brilliant practical joke, where neatness is
   correlated with cleverness, harmlessness, and surprise value.
   Example: the Caltech Rose Bowl card display switch circa 1961.  4.
   <real hack>: A crock (occasionally affectionate).  vt. 5. With
   "together", to throw something together so it will work.  6. To
   bear emotionally or physically.  "I can't hack this heat!" 7.  To
   work on something (typically a program).  In specific sense: "What
   are you doing?"  "I'm hacking TECO."  In general sense: "What
   do you do around here?"  "I hack TECO."  (The former is
   time-immediate, the latter time-extended.)  More generally, "I
   hack x" is roughly equivalent to "x is my major interest (or
   project)".  "I hack solid-state physics."  8. To pull a prank
   on.  See definition 3 and <hacker> (def #6).  9. v.i. To waste time
   (as opposed to <tool>).  "Watcha up to?"  "Oh, just hacking."
   10. <hack up>, <hack on>: To hack, but generally implies that the
   result is meanings 1-2.  11.  [UNIX] A dungeon game similar to
   <rogue> but more elaborate, distributed in C source over <USENET>
   and very popular at UNIX sites and on PC-class machines.  Recent
   versions are called `nethack'.  12. Short for <hacker>, which see.

   Constructions on this term abound.  They include: <happy hacking>: A
   farewell.  <how's hacking?>: A friendly greeting among hackers.
   <hack hack>: A somewhat pointless but friendly comment, often used
   as a temporary farewell.  For more on the meaning of <hack> see
   Appendix A.

<hack attack> [poss by analogy with "Big Mac Attack"] n. Nearly
   synonymous with <hacking run> though the latter implies an
   all-nighter more strongly.

<hack value> n. Often adduced as the reason or motivation for
   expending effort toward a seemingly useless goal, the point being
   that the accomplished goal is a hack.  For example, MacLISP has
   features for reading and printing roman numerals, which was
   installed purely for hack value.  As a musician once said of jazz,
   if you don't understand hack value there is no way it can be

<hacker> [originally, someone who makes furniture with an axe] n. 1. A
   person who enjoys learning the details of programming systems and
   how to stretch their capabilities, as opposed to most users who
   prefer to learn only the minimum necessary.  2. One who programs
   enthusiastically (even obsessively), or who enjoys programming
   rather than just theorizing about programming.  3. A person capable
   of appreciating <hack value>.  4. A person who is good at
   programming quickly.  Not everything a hacker produces is a hack.
   5. An expert at a particular program, or one who frequently does
   work using it or on it; example: "A UNIX hacker".  (Definitions 1
   to 5 are correlated, and people who fit them congregate.)  6.  An
   expert of any kind.  One might be an astronomy hacker, for example.
   7.  (deprecated) A malicious or inquisitive meddler who tries to
   discover information by poking around.  Hence "password hacker",
   "network hacker". See <cracker>.

<hack mode> n. 1. What one is in when hacking, of course. 2.  More
   specifically, a Zen-like state of total focus on The Problem which
   may be achieved when one is hacking.  Ability to enter such
   concentration at will correlates strongly with wizardliness; it is
   one of the most important skills learned during <larval stage>.
   Sometimes amplified as "deep hack mode". Being yanked out of hack
   mode (see <priority interrupt>) may be experienced as an almost
   physical shock, and the sensation of being in it is more than a
   little habituating.  The intensity of this experience is probably
   by itself sufficient explanation for the existence of hackers, and
   explains why many resist being promoted out of positions where they
   can do code.

<hacking run> [analogy with "bombing run" or "speed run"] n. A
   hack session extended long outside normal working times, especially
   one longer than 12 hours.  May cause you to "change phase the hard
   way" (see <phase>).

<hackish> /hak'ish/ adj. (also <hackishness> n.) 1. Being or involving
   a hack. 2. Of or pertaining to hackers or the hacker subculture.
   See also <true-hacker>.  It is better to be described as hackish by
   others than to describe oneself that way.  Hackers consider
   themselves somewhat of an elite, though one to which new members
   are gladly welcome.  It is a meritocracy based on ability.  There
   is a certain self-satisfaction in identifying yourself as a hacker
   (but if you claim to be one and are not, you'll quickly be labelled

<hackishness, hackitude> n.  The quality of being or involving a hack.
   (The word <hackitude> is considered silly; the standard term is

<hair> n. The complications which make something hairy.  "Decoding
   <TECO> commands requires a certain amount of hair."  Often seen in
   the phrase <infinite hair>, which connotes extreme complexity.
   Also in <hairiferous> (tending to promote hair growth): "GNU elisp
   encourages lusers to write complex editing modes."  "Yeah, it's
   pretty hairiferous all right." (or just: "Hair squared!")

<hairy> adj. 1. Overly complicated.  "<DWIM> is incredibly hairy."
   2.  Incomprehensible.  "<DWIM> is incredibly hairy."  3.  Of
   people, high-powered, authoritative, rare, expert, and/or
   incomprehensible.  Hard to explain except in context: "He knows
   this hairy lawyer who says there's nothing to worry about."

<HAKMEM> /hak'mem/ n. MIT AI Memo 239 (February 1972).  A legendary
   collection of neat mathematical and programming hacks contributed
   by many people at MIT and elsewhere.  (The title of the memo really
   is "HAKMEM", which is an acronym of sorts for "hacks memo".)
   Some of them are very useful techniques or powerful theorems, but
   most fall into the category of mathematical and computer trivia.  A
   sampling of the entries (with authors), slightly paraphrased:

   Item 41 (Gene Salamin) There are exactly 23,000 prime numbers less
   than 2 to the 18th power.

   Item 46 (Rich Schroeppel) The most *probable* suit
   distribution in bridge hands is 4-4-3-2, as compared to 4-3-3-3,
   which is the most *evenly* distributed.  This is because the
   world likes to have unequal numbers: a thermodynamic effect saying
   things will not be in the state of lowest energy, but in the state
   of lowest disordered energy.

   Problem 81 (Rich Schroeppel) Count the magic squares of order 5
   (that is, all the 5-by-5 arrangements of the numbers from 1 to 25
   such that all rows, columns, and diagonals add up to the same
   number).  There are about 320 million, not counting those that
   differ only by rotation and reflection.

   Item 174 (Bill Gosper and Stuart Nelson) 21963283741 is the only
   number such that if you represent it on the <PDP-10> as both an
   integer and a floating-point number, the bit patterns of the two
   representations are identical.

   HAKMEM also contains some rather more complicated mathematical and
   technical items, but these examples show some of its fun flavor.

<hakspek> /hak'speek/ n. Generally used term to describe a method of
   spelling to be found on many British academic bulletin boards and
   talker systems.  Syllables and whole words in a sentence are
   replaced by single ASCII characters which are phonetically similar
   or equivalent, whilst multiple letters are usually dropped.  Hence
   `for' becomes `4', `two', `too' and `to' become `2', `ck' becomes
   `k'.  "Before I see you tomorrow" becomes "b4 i c u 2moro".
   First appeared in London about 1986, and was probably caused by the
   slow speed of available talker systems, which operated on archaic
   machines with outdated operating systems, and no standard methods
   of commuinication.  Has become rarer nowadays.  See also <talk

<hamster> n. A particularly slick little piece of code that does one
   thing well; a small, self-contained hack.  The image is of a
   hamster happily spinning its exercise wheel.

<hand-hacking> n. 1. The practice of translating <hot spot>s from an
   <HLL> into custom hand-optimized assembler, as opposed to trying to
   coerce the compiler into generating better code.  Both the term and
   the practice are becoming uncommon.  See <tune>, <bum>; syn. with
   v.  <cruft>.  2. More generally, manual construction or patching of
   data sets that would normally be ground out by a translation
   utility and interpreted by another program, and aren't really
   designed to be read or modified by humans.

<handwave> 1. v. To gloss over a complex point; to distract a
   listener; to support a (possibly actually valid) point with
   blatantly faulty logic.  If someone starts a sentence with
   "Clearly..." or "Obviously..."  or "It is self-evident
   that...", you can be sure he is about to handwave.  The theory
   behind this term is that if you wave your hands at the right
   moment, the listener may be sufficiently distracted to not notice
   that what you have said is <bogus>.  Alternatively, if a listener
   does object, you might try to dismiss the objection with a wave of
   your hand. 2. n. The act of handwaving.  "Boy, what a handwave!"
   The use of this word is often accompanied by gestures: both hands
   up, palms forward, swinging the hands in a vertical plane pivoting
   at the elbows and/or shoulders (depending on the magnitude of the
   handwave); alternatively, holding the forearms still while rotating
   the hands at the wrist to make them flutter.  In context, the
   gestures alone can suffice as a remark; if a speaker makes an
   outrageous unsupported assumption, you might simply wave your hands
   in this way, as an accusation more eloquent than words could
   express that his logic is faulty.

<hang> v. 1. To wait for some event to occur; to hang around until
   something happens. "The program displays a menu and then hangs
   until you type a character." 2. More commonly, to wait for an
   event that will never occur. "The system is hanging because it
   can't read from the crashed drive". See <wedged>, <hung>.

<Hanlon's Razor> n. A "murphyism" parallel to Occam's Razor that
   reads "Never attribute to malice that which can be adequately
   explained by stupidity".  The derivation of the common title
   Hanlon's Razor is unknown; a similar epigram has been attributed to
   William James.  Quoted here because it seems to be a particular
   favorite of hackers, often showing up in <fortune cookie> files and
   the login banners of BBS systems and commercial networks.  This
   probably reflects the hacker's daily experience of environments
   created by the well-intentioned but shortsighted.

<hardwarily> /hard-weir'i-lee/ adv. In a way pertaining to hardware.
   "The system is hardwarily unreliable."  The adjective
   "hardwary" is *not* used.  See <softwarily>.

<hardwired> adj.  1. Insertion of data directly into a program, where
   it cannot be easily modified, as opposed to making provision for a
   <user> or hacker to modify the values easily.  2. In C, this is
   esp. applied to use of a literal instead of a preprocessor #define
   (see also <magic number>).  2. By extension, anything that is not
   modifiable, especially in the sense of customizable to one's
   particular needs or tastes.

<has the x nature> [seems to derive from Zen Buddhist koans of the
   form "Does an X have the Buddha-nature?"]  adj. Common hacker
   construction for `is an X', used for humorous emphasis.  "Anyone
   who can't even use a program with on-screen help embedded in it
   truly has the <loser> nature!"

<hash collision> [from the technical usage] n. When used of people,
   signifies a confusion in associative memory or imagination,
   especially a persistent one (see <thinko>). True story: one of us
   [ESR] was once on the phone with a friend about to move out to
   Berkeley.  When asked what he expected Berkeley to be like, the
   friend replied "Well, I have this mental picture of naked women
   throwing Molotov cocktails, but I think that's just a collision in
   my hash tables."  The variant "hash clash" is also reported.

<HCF> /aych-see-eff/ n. Mnemonic for "Halt and Catch Fire", any of
   several undocumented and semi-mythical machine instructions with
   destructive side-effects, supposedly included for test purposes on
   several well-known architectures going as far back as the IBM 360.
   The MC6800 microprocessor was the first for which the HCF opcode
   became widely known.  This instruction caused the processor to
   toggle a subset of the bus lines as rapidly as it can; in some
   configurations this can actually cause lines to burn up.

<heads down> [Sun] adj. Concentrating, usually so heavily and for so
   long that everything outside the focus area is missed.  See also
   <larval stage>, although it's not confined to fledgeling hackers.

<heartbeat> n. 1. The master clock signal propagated across an
   Ethernet; by extension, the time-baseline synchronization signal at
   the physical level of any network. 2. The `natural' oscillation
   frequency of a computer's clock crystal, before frequency division
   down to the machine's clock rate.  3. A signal emitted at regular
   intervals by software to demonstrate that it's still alive. Oppose

<heavy metal> [Cambridge] n. Syn. <big iron>.

<heavy wizardry> n. Code or designs which trade on a particularly
   intimate knowledge or experience of a particular operating system
   or language or complex application interface.  Distinguished from
   <deep magic>, which trades more on arcane *theoretical*
   knowledge.  Writing device drivers is heavy wizardry; so is
   interfacing to X (sense #2) without a toolkit.  Esp. found in
   comments of the form "Heavy wizardry begins here...".  Compare
   <voodoo programming>.

<heisenbug> /hie'sen-buhg/ [from Heisenberg's Uncertainty Principle in
   quantum physics] n. A bug which disappears or alters its behavior
   when one attempts to probe or isolate it.  Antonym of <Bohr bug>.
   In C, 9 out of 10 heisenbugs result from either <fandango on core>
   phenomena (esp. lossage related to corruption of the malloc
   <arena>) or errors which <smash the stack>.

<Helen Keller mode> n. State of a hardware or software system which is
   deaf, dumb, and blind, i.e. accepting no input and generating no
   output, usually due to an infinite loop or some other excursion
   into <deep space>.  (Unfair to the real Helen Keller, whose success
   at learning speech was triumphant.) See also <go flatline>.

<hello sailor>! interj. Occasional West Coast equivalent of <hello,
   world!>; seems to have originated at SAIL, later associated with
   the game <Zork> (which also included "hello aviator" and "hello

<hello wall!> excl. See <wall>.

<hello world!> interj. 1. The canonical minimal test message in the
   C/UNIX universe.  In folklore, the first program a C coder is
   supposed to write in a new environment is one that just prints
   "hello, world!" to standard output.  Environments that generate
   an unreasonably large executable for this trivial test or which
   require a <hairy> compiler-linker invocation to generate it are
   considered to <lose>. 2. Greeting uttered by a hacker making an
   entrance or requesting information from anyone present. "Hello,
   world! Is the <VAX> back up yet?"

<hidden flag> [scientific computation] n. A extra option added to a
   routine without changing the calling sequence.  For example,
   instead of adding an explicit input variable to instruct a routine
   to give extra diagnostic output, the programmer might just add a
   test for some otherwise meaningless feature of the existing inputs,
   such as a negative mass.  Liberal use of hidden flags can make a
   program very hard to debug and understand.

<high bit> n. 1. See <meta bit>. Also meaning most significant part of
   something other than a data byte, e.g. "Spare me the whole saga,
   just give me the high bit."

<high moby> /hie mohb'ee/ n. The high half of a stock <PDP-10>'s
   address space; the other half was of course the low moby.  This
   usage has been generalized in a way that has outlasted the
   <PDP-10>; for example, at the 1990 Washington D.C Area Science
   Fiction Conclave (DISCLAVE) when a miscommunication resulted in two
   separate wakes being held in commemoration of the shutdown of MIT's
   last <ITS> machines, the one on the upper floor was dubbed the high
   moby and the other the low moby.  All parties involved grokked this
   instantly.  See <moby>.

<highly> [scientific computation] adv. The preferred modifier for
   overstating an understatement.  As in: <highly nonoptimal>, the
   worst possible way to do something; <highly nontrivial>, either
   impossible or requiring a major research project; <highly
   nonlinear>, completely erratic and unpredictable; <highly
   nontechnical>, drivel written for <luser>s, oversimplified to the
   point of being misleading or incorrect (compare <drool-proof
   paper>).  In other computing cultures, postfixing of <in the
   extreme> might be preferred.

<hirsute> adj. Occasionally used humorously as a synonym for <hairy>.

<HLL> /aych-el-el/ n. [High-Level Language (as opposed to assembler)]
   Found primarily in email and news rather than speech.  Rarely, the
   variants `VHLL' and `MLL' are found.  VHLL = `Very-High-Level
   Language' and is used to describe a <BONDAGE-AND-DISCIPLINE
   LANGUAGE> that the speaker happens to like; Prolog and Backus's FP
   are often called VHLLs. `MLL' = `Medium-Level Language' and is
   sometimes used half-jokingly to describe C, alluding to its
   `structured-assembler' image.  See also <languages of choice>.

<hog> n.,vt. Favored term to describe programs or hardware which seem
   to eat far more than their share of a system's resources, esp.
   those which noticeably degrade general timesharing response.
   *Not* used of programs which are simply extremely large or
   complex or which are merely painfully slow themselves (see <pig,
   run like a>). More often than not encountered in qualified forms,
   e.g. "memory hog", "core hog", "hog the processor", "hog the
   disk". Example: "A controller that never gives up the I/O bus
   gets killed after the bus hog timer expires."

<holy wars> [from <USENET>, but may predate it] n.  <flame war>s over
   <religious issues>.  The 1980 paper by Danny Cohen that popularized
   the terms <big-endian> and <little-endian> in connection with the
   LSB-first/MSB-first controversy was entitled `On Holy Wars and
   a Plea for Peace'. Other perennial Holy Wars have included: <EMACS>
   vs.  <VI>, my personal computer vs. everyone else's personal
   computer, <ITS> vs. <UNIX>, <UNIX> vs. <VMS>, <BSD> UNIX vs. <USG>
   UNIX, C vs.  Pascal, etc. etc. etc.  The characteristic that
   distinguishes <holy wars> from normal technical disputes is that
   (regardless of the technical merits of the case on either side)
   most participants spend their time trying to pass off personal
   value choices and cultural attachments as objective technical

<hook> n. An extraneous piece of software or hardware included in
   order to simplify later additions or changes by a user.  For
   instance, a PDP-10 program might execute a location that is
   normally a JFCL, but by changing the JFCL to a PUSHJ one can insert
   a debugging routine at that point.  As another example, a simple
   program that prints numbers might always print them in base ten,
   but a more flexible version would let a variable determine what
   base to use; setting the variable to 5 would make the program print
   numbers in base five.  The variable is a simple hook.  An even more
   flexible program might examine the variable, and treat a value of
   16 or less as the base to use, but treat any other number as the
   address of a user-supplied routine for printing a number.  This is
   a very powerful hook; one can then write a routine to print numbers
   as roman numerals, say, or as Hebrew characters, and plug it into
   the program through the hook.  Often the difference between a good
   program and a superb one is that the latter has useful hooks in
   judiciously chosen places.  Both may do the original job about
   equally well, but the one with the hooks is much more flexible for
   future expansion of capabilities.

<home box> n. A hacker's personal machine, especially one he owns.
   "Yeah?  Well, *my* home box runs a full 4.2BSD, so there!"

<hose> 1. vt. To make non-functional or greatly degraded in
   performance, as in "That big ray-tracing program really hoses the
   system."  See <hosed>.  2. n. A narrow channel through which data
   flows under pressure.  Generally denotes data paths in a system
   that represent performance bottlenecks.  3.  Cabling, especially
   thick Ethernet cable.  This is sometimes called "bit hose" or
   "hosery" (play on "hosiery") or "etherhose".  See also
   <washing machine>.

<hosed> adj. Same as <down>.  Used primarily by UNIX hackers.
   Humorous: also implies a condition thought to be relatively easy to
   reverse.  Probably derived from the Canadian slang `hoser'
   popularized by the Bob and Doug skits on SCTV. See <hose>.

   There is a story that a Cray which had been experiencing periodic
   difficulties once crashed, and it was announced to have been
   <hosed>.  It was discovered that the crash was due to the
   disconnection of some coolant hoses.  The problem was corrected, and
   users were then assured that everything was OK because the system
   had been rehosed.  [This is an excellent example of hackish
   wordplay --- ESR].

<hot spot> n. 1. [primarily C/UNIX programmers, but spreading] n.  In
   most programs, less than 10% of the code eats 90% of the execution
   time; if one were to graph instruction visits versus code
   addresses, one would typically see a few huge spikes amidst a lot
   of low-level noise.  Such spikes are called "hot spots" and are
   good candidates for micro-optimization or <hand-hacking>.  The term
   is especially used of tight loops and recursions in the code's
   central algorithm, as opposed to (say) initial set-up costs or
   large but infrequent I/O operations.  See <tune>, <bum>,
   <hand-hacking>.  2. The active location of a cursor on a bit-map
   display.  "Put the mouse's hot spot on the `ON' widget and click
   the left button."

<house wizard> [prob. from ad-agency lingo, cf. `house freak'] n. A
   lone hacker occupying a technical-specialist, R&D or systems
   position at a commercial shop.  A really effective house wizard can
   have influence out of all proportion to his/her ostensible rank and
   still not have to wear a suit.  Used esp. of UNIX experts.  The
   term <house guru> is equivalent.

<HP-SUX> /aych pee suhx/ n. Unflattering hackerism for HP-UX,
   Hewlett-Packard's UNIX port.  Features some truly unique bogosities
   in the filesystem internals and elsewhere that occasionally create
   portability problems.  HP-UX is often referred to as "hockey-pux"
   inside HP, and one outside correspondent claims that the proper
   pronunciation is /aych-pee ukkkhhhh/ as though one were spitting.
   See also <Telerat>, <sun-stools>, <terminak>.

<humma> excl. A filler word used on various "chat" and "talk"
   programs when you had nothing to say but felt that it was important
   to say something.  The word apparently originated (at least with
   this definition) on the MECC Timeshare System (MTS) a now-defunct
   educational time-sharing system running in Minnesota during the
   1970s and early '80s, but was later sighted on early UNIX systems.

<humongous> /hyoo-mohng'gus/ alt. <humingous> (hyoo-muhng'gus) See

<HUMOR, HACKER> n. A distinctive style of shared intellectual humor
   found among hackers, having the following marked characteristics:

   1) Fascination with form-vs.-content jokes, paradoxes, and humor
   having to do with confusion of metalevels (see <meta>). One way to
   make a hacker laugh: hold an index card in front of him/her with
   "THIS IS GREEN" written on it in bold red ink, or vice-versa
   (note, however, that this is only funny the first time).

   2) Elaborate deadpan parodies of large intellectual constructs such
   as specifications (see <write-only memory>), standards documents,
   language descriptions (see <INTERCAL>) and even entire scientific
   theories (see <quantum bogodynamics>, <computron>).

   3) Jokes which involve screwily precise reasoning from bizarre,
   ludicrous or just grossly counter-intuitive premises.

   4) Fascination with puns and wordplay.

   5) A fondness for apparently mindless humor with subversive
   currents of intelligence in it, for example: old Warner Brothers
   and Rocky & Bullwinkle cartoons, Charlie Chaplin movies, the B-52s,
   and Monty Python's Flying Circus.  Humor which combines this trait
   with elements of high camp and slapstick is especially favored.

   6) References to the symbol-object antinomies and associated ideas
   in Zen Buddhism and (less often) Taoism.  See <has the x nature>,
   <Discordianism>, <zen>, <ha ha only serious>, <AI koans>.

   See also <filk>; <retrocomputing>; and Appendix B.  If you have an
   itchy feeling that all six of these traits are really aspects of
   one thing that is incredibly difficult to talk about exactly, you
   are a) correct and b) responding like a hacker.  These traits are
   also recognizable (though in a less marked form) throughout

<hung> [from "hung up"] adj. Equivalent to <wedged>, q.v. but more
   common at UNIX/C sites.  Not generally used of people.  Syn. with
   <locked up>, <wedged>; compare <hosed>.  See also <hang>.

<hungus> /hung'g@s/ [perhaps related to current slang "humongous";
   which one came first (if either) is unclear] adj. Large, unwieldy,
   usually unmanageable.  "TCP is a hungus piece of code."  "This
   is a hungus set of modifications."

<hyperspace> (hie'per-spays) n. A memory location within a virtual
   memory machine that is many, many megabytes (or gigabytes) away
   from where the program counter should be pointing, usually
   inaccessible because it is not even mapped in. "Another core
   dump... looks like the program jumped off to hyperspace somehow."
   This usage is from the SF notion of a spaceship "jumping into
   hyperspace", that is, taking a shortcut through higher-dimensional
   space --- in other words, leaving this universe.

                                {= I =}

<IBM> /ie bee em/ Inferior But Marketable; It's Better Manually;
   Insidious Black Magic; It's Been Malfunctioning; Incontinent Bowel
   Movement; and a near-<infinite> number of even less complimentary
   expansions, including "International Business Machines". See
   <TLA>.  These abbreviations illustrate the considerable antipathy
   most hackers have long felt for the "industry leader" (see <fear
   and loathing>).  What galls hackers about most IBM machines above
   the PC level isn't so much that they're underpowered and overpriced
   (though that counts against them) but that the designs are
   incredibly archaic, crufty and <elephantine> and you can't
   *fix* them --- source code is locked up tight and programming
   tools are expensive, hard to find, and bletcherous to use once
   you've found them.  With the release of the UNIX-based RIOS family
   this may have begun to change --- but then, we thought that when
   the PC-RT came out, too.  In the spirit of universal peace and
   brotherhood, this lexicon now includes a number of entries marked
   `IBM'; these derive from a rampantly unofficial jargon list
   circulated among IBM's own beleaguered hacker underground.

<ice> [from William Gibson's cyberpunk SF: notionally, "Intrusion
   Countermeasure Electronics"] Security software (in Gibson's
   original, software that responds to intrusion by attempting to
   literally kill the intruder).  Also, <icebreaker>: a program
   designed for cracking security on a system.  Neither term is in
   serious use yet as of 1990, but many hackers find the metaphor
   attractive and they may be in the near future.

<ill-behaved> adj. 1. [numerical analysis] Said of an algorithm or
   computational method that tends to blow up due to accumulated
   roundoff error or poor convergence properties.  2. Software which
   bypasses the defined <OS> interfaces to do things (like screen,
   keyboard and disk I/O) itself, often in a way that depends on the
   hardware of the machine it is running on or which is nonportable or
   incompatible with other pieces of software.  In the IBM PC/MS-DOS
   world, there is a folk theorem (nearly true) to the effect that
   (due to gross inadequacies and performance penalties in the OS
   interface) all interesting applications are ill-behaved.  Oppose
   <well-behaved>, compare <PC-ism>.  See <mess-dos>.

<IMHO> [from SF fandom via USENET] Written acronym for In My Humble
   Opinion.  Example: "IMHO, mixed-case C names should be avoided, as
   mistyping something in the wrong case can cause hard-to-detect
   errors --- and they look too Pascalish anyhow."  Also seen in
   variant forms such as IMNSHO (In My Not-So-Humble Opinion) and IMAO
   (In My Arrogant Opinion).

<in the extreme> adj. A preferred emphasizing suffix for many hackish
   terms. See for example <obscure in the extreme> under <obscure>,
   and compare <highly>.

<incantation> n. Any particularly arbitrary or obscure command that
   must be muttered at a system to attain a desired result.  Not used
   of passwords or other explicit security features.  Especially used
   of tricks that are so poorly documented they must be learned from a
   <wizard>.  E.g. "This compiler normally locates initialized data
   in the data segment, but if you mutter the right incantation they
   will be forced into text space". See <mutter>.

<include> v. [USENET] 1. To duplicate a portion (or whole) of
   another's message (typically with attribution to the source) in a
   reply or followup, for clarifying the context of one's response.
   2. A directive; to explicitly command the preprocessor to include a
   file.  3. Derived from C: #include <disclaimer.h> has appeared in
   <sig block>s to denote a `standard' dislaimer file.

<include war> n. Excessive multi-leveled including within a discussion
   thread (ie of the same subject), to annoy readers.  In a forum such
   as USENET, with high traffic newsgroups, this can lead to <flame>s
   and the urge to start a <kill file>.

<infinite> adj. Consisting of a large number of objects; extreme.
   Used very loosely as in: "This program produces infinite
   garbage."  "He is an infinite loser."  This is an abuse of the
   word's mathematical meaning.  The term "semi-infinite" denoting
   an immoderately large amount of some resource is also heard.
   "This compiler is taking a semi-infinite amount of time to
   optimize my program".  See also <semi->.

<infinity> n. 1. The largest value that can be represented in a
   particular type of variable (register, memory location, data type,
   whatever).  2. <minus infinity> The smallest such value.  Note that
   this is different from <time t equals minus infinity>, which is
   closer to a mathematician's usage of infinity.

<infant mortality> n. It is common lore among hackers that the chances
   of sudden hardware failure drop off exponentially with a machine's
   time since power-up (that is until the relatively distant time at
   which mechanical wear in I/O devices and thermal-cycling stress in
   components has accumulated enough for the machine to start going
   senile). Up to half of all chip-and-wire failures happen within a
   new system's first few weeks; such failures are often referred to
   as "infant mortality" problems (or, occasionally, as "sudden
   infant death syndrome").

<insanely great> adj. [Mac Community, from Steve Jobs; also BSD UNIX
   people via Bill Joy] Something so incredibly <elegant> that it is
   imaginable only to someone possessing the greatest of

<INTERCAL> /in't@r-kal/ [said by the authors to stand for "Compiler
   Language With No Pronounceable Acronym"] n. A computer language
   designed by Don Woods and James Lyon in 1972. INTERCAL is purposely
   different from all other computer languages in all ways but one; it
   is purely a written language, being totally unspeakable.  An
   excerpt from the INTERCAL Reference Manual will make the style of
   the language clear.  In most languages, if you wanted the variable
   A to have the value 65536, you would write something like

     LET A = 65536;

   The INTERCAL Reference Manual, however, explains that "It is a
   well-known and oft-demonstrated fact that a person whose work is
   incomprehensible is held in high esteem.  For example, if one were
   to state that the simplest way to store a value of 65536 in a
   32-bit INTERCAL variable is:

     DO :1 <- #0$#256

   any sensible programmer would say that that was absurd.  Since this
   is indeed the simplest method, the programmer would be made to look
   foolish in front of his boss, who would of course have happened to
   turn up, as bosses are wont to do.  The effect would be no less
   devastating for the programmer having been correct."  INTERCAL has
   many other peculiar features designed to make it even more
   unspeakable.  The Woods/Lyons implementation was actually used by
   many (well, at least several) people at Princeton.  The language
   has been recently re-implemented as C-INTERCAL and is consequently
   enjoying an unprecedented level of unpopularity; there is even an
   alt.lang.intercal newsgroup devoted to the study and ...
   appreciation of the language on USENET.

<interesting> adj. In hacker parlance, this word is not simply
   synonymous with "intriguing", but has strong connotations of
   "annoying", or "difficult", or both.  Hackers relish a
   challenge.  Oppose <trivial>.

<Internet address> n. An `absolute' network address of the form
   foo@bar.baz, where foo is a user name, bar is a <sitename>, and
   baz is a `domain' name, possibly including periods itself.
   Contrasts with <bang path>, q.v.; see also <network, the> and
   <network address>.  All Internet machines and most UUCP sites can
   now resolve these addresses, thanks to a large amount of
   behind-the-scenes magic and PD software written since 1980 or so.
   See also <bang path>.

<interrupt> interj. 1. On a computer, an event which interrupts normal
   processing and temporarily diverts flow-of-control through an
   "interrupt handler" routine.  See also <trap>.  2. A request for
   attention from a hacker.  Often explicitly spoken. "Interrupt ---
   have you seen Joe recently?".  See <priority interrupt>.

<interrupts locked out> adj. When someone is ignoring you.  In a
   restaurant, after several fruitless attempts to get the waitress's
   attention, a hacker might well observe that "She must have
   interrupts locked out."  Variations of this abound; "to have one's
   interrupt mask bit set" is also heard.

<iron> n. Hardware, especially older/larger hardware of mainframe
   class with big metal cabinets housing relatively low-density
   electronics (but also used of modern supercomputers). Often in the
   phrase <big iron>.  Oppose <silicon>.  See also <dinosaur>.

<iron box> [UNIX/Internet] n. A special environment set up to trap a
   <cracker> logging in over remote or network connections long enough
   so he can be traced.  May include a specially-gimmicked <shell>
   restricting the hacker's movements in unobvious ways, and `bait'
   files designed to keep him interested and logged on.  See also
   <back door>, <firewall machine>, <venus flytrap> and Clifford
   Stoll's account of how he made and used one (see Appendix B).

<ironmonger> [IBM] n. A hardware specialist.  Derogatory.  Compare
   <sandbender>, <polygon pusher>.

<ITS> /ie-tee-ess/ n. Incompatible Time-Sharing System, an influential
   but highly idiosyncratic operating system written for PDP-10s at
   MIT and long used at the MIT AI lab; much AI-hacker slang derives
   from ITS folklore.  After about 1982 most actual work was shifted
   to newer machines, with the remaining ITS boxes run essentially as
   a hobby and service to the hacker community.  The shutdown of the
   lab's last ITS machine in May 1990 marked the end of an era and
   sent old-time hackers into mourning nationwide.  The Royal
   Institute of Technology in Sweden is maintaining one `live'  ITS
   site at its computer museum (right next to the only TOPS-10 system
   still on the Internet), so ITS is still alleged to hold the record
   for OS in longest continuous use.  See Appendix A.

<IWBNI> [acronym] It Would Be Nice If.  No pronunciation, as this is
   never spoken, only written.  Compare <WIBNI>.

<IYFEG> [USENET] Abbreviation for "Insert Your Favourite Ethnic
   Group".  Used as a meta-name when telling racist jokes in email to
   avoid offending anyone.

                                {= J =}

<J. Random> /jay rand'm/ n. [generalized from <J. Random Hacker>,
   q.v.]  Arbitrary; ordinary; any one; "any old".  "Would you let
   J.  Random Loser marry your daughter?".  <J. Random> is
   often prefixed to a noun to make a name out of it.  It means
   roughly "some particular" or "any specific one".  The most
   common uses are "J. Random Hacker, "J. Random Loser" and "J.
   Random Nerd" ("Should J. Random Loser be allowed to <gun> down
   other people?"), but it can be used just as an elaborate version
   of <random> in any sense.

<J. Random Hacker> [MIT] /jay rand'm hak'r/ n. A mythical figure like
   the Unknown Soldier; the archetypal hacker nerd.  See <random>,
   <Suzie COBOL>.  This may originally have been inspired or
   influenced by `J.  Fred Muggs', a show-biz chimpanzee whose name
   was a household word back in the days of the MIT Model Railroad

<jaggies> /jag'eez/ n. The `stairstep' effect observable when an edge
   (esp. a linear edge of slope far from a multiple of 45 degrees) is
   rendered on a pixel device (as opposed to a vector display).

<JCL> [ex-IBM] 1. IBM's ultimately <rude> "Job Control Language."
   JCL was the script language used to control the execution of
   programs in IBM's batch systems.  JCL had a very <fascist> syntax,
   and would, for example, <barf> if two spaces appeared where it
   expected one.  Most programmers who were confronted with JCL would
   simply copy a working file (or card deck), changing the file names.
   Someone who actually understood and generated unique JCL was
   regarded with the mixed respect which one gives to someone who
   memorizes the phone book.  2. Any very <rude> software that a
   hacker is expected to use.  "That's as bad as JCL."  Often used
   without having experienced it, as is <COBOL>.  See also <IBM>,
   <fear and loathing>.

<JFCL> /jif'kl/ or /jaf'kl/ v., obs. To cancel or annul something.
   "Why don't you jfcl that out?" The fastest do-nothing instruction
   on the PDP-10 happened to be JFCL, which stands for "Jump if Flag
   set and then CLear the flag"; this does something useful, but is a
   very fast no-operation if no flag is specified.  Geoff Goodfellow,
   one of the jargon-1 compilers, once had JFCL on the license plate
   of his BMW.  Usage: rare except among old-time PDP10 hackers.

<jiffy> n. 1. The width of one tick of the system clock on the
   computer (see <tick>).  Often 1 AC cycle time (1/60 second in the
   U.S. and Canada, 1/50 most other places) but more recently 1/100
   sec has become common.  2.  Confusingly, the term is sometimes also
   used for a 1-millisecond <wall time> interval.  "The swapper runs
   every six jiffies" means that the virtual memory management
   routine is executed once for every six ticks of the clock, or about
   ten times a second.  3.  Indeterminate time from a few seconds to
   forever. "I'll do it in a jiffy" means certainly not now and
   possibly never.  This is a bit contrary to the more widespread use
   of the word.

<jock> n. 1. Programmer who is characterized by large and somewhat
   brute force programs.  See <brute force>. 2. When modified by
   another noun, describes a specialist in some particular computing
   area.  The compounds `compiler jock' and `systems jock' seem to be
   the best established examples of this.

<joe code> /joh kohd/ [said to commemmorate a notoriously bad coder
   named Joe at Lawrence Berkeley Laboratory] n. Badly written,
   possibly buggy source code.  Correspondents wishing to remain
   anonymous have fingered a particular Joe and observed that usage
   has drifted slightly; they described his code as "overly <tense>
   and unmaintainable".  "Perl may be a handy program, but if you
   look at the source, it's complete joe code."

<JR[LN]> /jay ahr en/, /jay ahr el/ n. The names JRN and JRL were
   sometimes used as example names when discussing a kind of user ID
   used under <TOPS-10>; they were understood to be the initials of
   (fictitious) programmers named "J. Random Nerd" and "J. Random
   Loser" (see <J. Random>).  For example, if one said "To log in,
   type log one comma jay are en" (that is, "log1,JRN"), the
   listener would have understood that he should use his own computer
   id in place of "JRN".

                                {= K =}

<K> [from <kilo->] /kay/ n.  Kilobyte.  Similarly, at least, meg
   (/meg/) and gig (/gig/) for megabyte and gigabyte.  Also written
   KB, MB, GB respectively.  See also <kilo>.

<K&R> [Kernighan and Ritchie] n. Brian Kernighan & Dennis Ritchie's
   "The C Programming Language", esp. the classic and influential
   first edition (Prentice-Hall 1978, ISBN 0-113-110163-3).  Also
   called the <White Book>.  See also <Red Book>, <Green Book>, <Blue
   Book>, <Purple Book>, <Silver Book>, <Orange Book>, <Pink-Shirt
   Book>, <Dragon Book>, <Aluminum Book>.

<kahuna> /k@-hoo'nuh/ [IBM, from the Hawaiian title for a shaman] n.
   Synonym for <wizard>, <guru>.

<ken> /ken/ n. A flaming user.  This noun was in use by the Software
   Support group at Symbolics because the two greatest flamers in the
   user community were both named Ken.

<kgbvax> /kay-jee-bee-vaks/ n. See <kremvax>.

<kill file> [USENET] n.  Per-user file used by some <USENET> reading
   programs to discard summarily (without presenting for reading)
   articles which match some particularly uninteresting (or unwanted)
   patterns of subject, author, or other header lines.  Thus to "add
   a person (or subject) to one's kill file" is to arrange for that
   person to be ignored by your newsreader in future.  By extension,
   it may be used for a decision to ignore the person or subject in
   other media.

<killer micro> [popularized by Eugene Brooks] n. A
   microprocessor-based machine that infringes on mini, mainframe or
   supercomputer performance turf.  Often heard in "No one will
   survive the attack of the killer micros!", the battle cry of the
   downsizers.  Used esp. of RISC architectures.

<killer poke> n. A recipe for inducing hardware damage on a machine
   via insertion of invalid values in a memory-mapped control
   register; used esp. of various fairly well-known tricks on MMU-less
   <bitty boxes> like the IBM PC and Commodore PET that can overload
   and trash analog electronics in the monitor.  See also <HCF>.

<kilo-> [from metric measure] prefix.  Denotes multiplication by 1024,
   the power of 2 closest to 1000, rather than by the usual 1000.
   Similarly the higher metric prefixes denote multiplication by
   powers of 1024 rather than of 1000: mega- meaning 1048576, giga-
   meaning 1073741824, tera- meaning 1099511627776, peta- meaning
   1125899906842624, and exa- meaning 1152921504606846976.  The last
   two have not actually been observed, yet.  Usage: especially with
   "bytes", but also with anything else perceived to naturally come in
   units that are powers of 2.

   Confusion of 1000 and 1024, for example describing memory in units
   of 524K (see K) instead of 512K, is a sure sign of the

<kluge> /klooj/ alt. kludge /kluhj/ [from the German "klug", clever]
   (`klooj' is the original pronunciation, more common in the US;
   `kluhj' is reported more common in England).  n. 1. A Rube Goldberg
   (or Heath Robinson) device in hardware or software. (A long-ago
   Datamation article said: "An ill-assorted collection of poorly
   matching parts, forming a distressing whole.")  2. n.  A clever
   programming trick intended to solve a particular nasty case in an
   expedient, if not clear, manner.  Often used to repair bugs.  Often
   involves <ad-hockery> and verges on being a <crock>.  3.  Something
   that works for the wrong reason.  4.  vt. To insert a kluge into a
   program.  "I've kluged this routine to get around that weird bug,
   but there's probably a better way."  Also "kluge up"; "I've
   kluged up this routine...,etc." .  5. <kluge around>: To avoid by
   inserting a kluge.  6.  [WPI] A feature which is implemented in a
   <rude> manner.

   Note that a plurality of hackers pronounce this word /klooj/ but
   spell it incorrectly as `kludge'.  Some observers consider this
   appropriate in view of its meaning.

<Knights of the Lambda Calculus> n. A semi-mythical organization of
   wizardly LISP and Scheme hackers (the name refers to a mathematical
   formalism invented by Alonzo Church with which LISP is intimately
   connected). There is no enrollment list and the criteria for
   induction are unclear, but one well-known LISPer has been known to
   give out buttons and, in general, the *members* know who they

<Knuth> [Dold Knuth's "The Art of Computer Programming"] n. The
   reference that answers all questions about data structures or
   algorithms.  A safe answer when you do not know, as in "I think
   you can find that in Knuth."  Contrast <literature, the>.  See also

<kremvax> /krem-vaks/ [From the then large number of <USENET> <VAXen>
   with names of the form "foovax"] n.  A fictitious USENET site at
   the Kremlin, announced on April 1, 1984, in a posting ostensibly
   from Soviet leader Konstantin Chernenko.  The posting was actually
   forged by Piet Beertema as an April Fool's joke.  Other sites
   mentioned in the hoax were moskvax and <kgbvax>, which now seems to
   be the one by which it is remembered.  This was probably the
   funniest of the many April Fool's forgeries perpetrated on USENET
   (which has negligible security against them), because the notion
   that USENET might ever penetrate the Iron Curtain seemed so totally
   absurd at the time.  But in fact, the first genuine site in Moscow
   ( joined USENET only 6 years later --- and some readers
   needed convincing that it wasn't a hoax.

   [Ed. note: Vadim Antonov (, the major poster from up to at least the end of 1990, was well acquainted with
   the kremvax hoax and referred to it in his own postings --- even to
   the extent of twitting a number of credulous netters on
   alt.folklore.computers by blandly "admitting" that *he* was
   a hoax! Mr. Antonov, BTW, also contributed the Russian-language
   material for this File --- ESR]

                                {= L =}

<lace card> n. obs. A Hollerith card with all holes punched (also
   called a <whoopee card>).  Card readers jammed when they got to one
   of these, as the resulting card had too little structural strength
   to avoid buckling inside the mechanism.  When some practical joker
   fed a <lace card> through the reader you needed to clear the jam
   with a card knife --- which you used on the joker first.

<language lawyer> n. A person, usually an experienced or senior
   software engineer, who is intimately familiar with many or most of
   the numerous syntactic and semantic restrictions (both useful and
   esoteric) applicable to one or more computer programming languages.
   Compare <wizard>.

<languages of choice> n. C or LISP. Essentially all hackers know one
   of these and most good ones are fluent in both.  Smalltalk and
   Prolog are popular in small but influential communities.  Assembler
   used to be a language of choice, but is generally no longer
   considered interesting or appropriate for anything but compiler
   code generation and a few time-critical uses in systems programs.
   There is also a rapidly dwindling category of older hackers with
   FORTRAN as their language of choice; they often prefer to be known
   as <real programmers>, and other hackers consider them a bit odd.

   Most hackers tend to frown at languages like Pascal and Ada which
   don't give them the near-total freedom considered necessary for
   hacking (see <bondage-and-discipline language>) and to regard
   everything that's even remotely connected with COBOL as a total

<larval stage> n. Describes a period of monomaniacal concentration on
   coding apparently passed through by all fledgling hackers.  Common
   symptoms include: the perpetration of more than one 36-hour
   <hacking run> in a given week, neglect of all other activities
   including usual basics like food and sex, and a chronic case of
   advanced bleary-eye.  Can last from six months to two years, with
   the apparent median being around eighteen months.  A few so
   afflicted never resume a more `normal' life, but the ordeal seems
   to be necessary to produce really wizardly (as opposed to merely
   competent) programmers.  A less protracted and intense version of
   larval stage (typically lasting about a month) may recur when
   learning a new <OS> or programming language.

<lase> /layz/ vt. To print a given document via a laser printer. "OK,
   let's lase that sucker and see if all those graphics-macro calls
   did the right things."

<laser chicken> n. Kung Pao Chicken, a standard Chinese dish
   containing chicken, peanuts, and bell peppers in a spicy pepper-oil
   sauce.  A few hackers call it "laser chiicken" for two reasons;
   it can <zap> you just like a laser, and the pepper-oil sauce has a
   red color reminiscent of some laser beams.

   In a variation on this theme, it is reported that one group of
   Australian hackers have redesignated the common dish "lemon
   chicken" as "Chernobyl Chicken".  The name is derived from the
   colour of the dish, which is considered bright enough to glow in
   the dark (much like some of the fabled inhabitants of Chernobyl).

<LDB> /l@d'd@b/ [from the PDP-10 instruction set] v. To extract from
   the middle.  This usage has been kept alive by Common LISP's
   function of the same name.  See also <DPB>.

<leak> n. With qualifier, one of a class of resource-management bugs
   that occur when resources are not freed properly after operations
   on them are finished, leading to eventual exhaustion as new
   allocation requests come in.  <memory leak> and <fd leak> have
   their own entries; one might also refer, say, to a "window handle
   leak" in a window system.

<leaky heap> [Cambridge] n. Syn. <memory leak>.

<LERP> /lerp/ v.,n. Quasi-acronym for Linear Interpolation, used as a
   verb or noun for the operation.  Ex. Bresenham's algorithm lerps
   incrementally between the two endpoints of the line.

<lexer> /lek'sr/ n. Common hacker shorthand for "lexical analyzer",
   the input-tokenizing stage in the parser for a language. "Some C
   lexers get confused by the old-style compound ops like =-".

<life> n. 1. A cellular-automata game invented by John Horton Conway,
   and first introduced publicly by Martin Gardner (Scientific
   American, October 1970). Many hackers pass through a stage of
   fascination with it, and hackers at various places contributed
   heavily to the mathematical analysis of this game (most notably
   Bill Gosper at MIT; see <Gosperism>).  When a hacker mentions
   "life", he is much more likely to mean this game than the
   magazine, the breakfast cereal, or the human state of existence.
   2. The opposite of <USENET>. As in "Get a life!".

<like kicking dead whales down the beach> adj. A slow and disgusting
   process.  First popularized by a famous quote about the difficulty
   of getting work done under one of IBM's mainframe OSs. "Well, you
   *could* write a C compiler in COBOL, but it would be like
   kicking dead whales down the beach."

<line eater, the> [USENET] n. 1. A bug in some now-obsolete versions
   of the netnews software used to eat up to 512 bytes of the article
   text.  The bug was triggered by having the text of the article
   start other than as the first character of the line.  This bug was
   quickly personified as a mythical creature called "the line
   eater", and postings often included a dummy line of "line eater
   food".  Ironically, line eater food that had whitespace before it
   was eaten along with the following text the food was supposed to
   protect, and line eater food that didn't have whitespace before it
   isn't eaten, since the bug is avoided.  The practice of
   "sacrificing to the line eater" continued for some time after the
   bug had been <nailed to the wall>, and is still humorously referred
   to.  The bug itself is still (in mid-1990) occasionally reported to
   be lurking in some mail-to-netnews gateways.  2. The mythical NSA
   trawling program sometimes assumed to be reading <USENET> for the
   U.S. Government's spooks.  Some netters put loaded phrases like
   `Uzi' `nuclear materials' `Palestine' `cocaine' and `assassination'
   in their <sig block>s in an attempt to confuse and overload the
   creature.  The <GNU> version of <EMACS> actually has a command that
   randomly generates a lot of words like that into your edited text.

<line starve> [MIT] 1. vi. To feed the paper through the terminal the
   wrong way by one line (most terminals can't do this!).  On a
   display terminal, to move the cursor up to the previous line of the
   screen.  Example: "To print X squared, you just output X, line
   starve, 2, line feed."  (The line starve causes the 2 to appear on
   the line above the X, and the line feed gets back to the original
   line.) 2. n. A "character" (or character sequence) that causes a
   terminal to perform this action.  Unlike "line feed", "line
   starve" is *not* standard ASCII terminology.  Even among
   hackers it is considered a bit silly.  3. [proposed] A sequence
   like \c (used in System V echo, as well as nroff/troff) which
   suppresses a line feed that would normally implicitly be emitted.

<link-dead> [popularized by MUD] adj. 1. A lost Telnet/MUD connection.
   v. 2. A deliberate act, with ulterior motives, to close a

<link farm> [UNIX] n. A directory tree that contains many links to
   files in another, master directory tree of files.  Link farms save
   space when maintaining several nearly identical copies of the same
   source tree, e.g. when the only difference is
   architecture-dependent object files.  Example use: `Let's freeze
   the source and then rebuild the FROBOZZ-3 and FROBOZZ-4 link
   farms.'  Link farms may also be used to get around restrictions on
   the number of -I arguments on older C preprocessors.

<lint> [from UNIX's `lint(1)', named perhaps for the bits of
   fluff it picks from programs] 1. v. To examine a program closely
   for style, language usage, and portability problems, esp. if in C,
   esp. if via use of automated analysis tools, most esp. if the UNIX
   utility `lint(1)' is used.  This term used to be restricted to
   use of `lint(1)' itself but (judging by references on USENET)
   has become a shorthand for `desk-check' at some non-UNIX shops,
   even in some languages other than C. See also <delint>.  2. Excess
   verbiage in a document, as in "this draft has too much lint".

<lion food> [IBM] n. Middle management or HQ staff (by extension,
   administrative drones in general). From an old joke about two lions
   who, escaping from the zoo, split up to increase their chances but
   agreed to meet after two months.  When they do meet, one is skinny
   and the other overweight.  The thin one says "How did you manage?
   I ate a human just once and they turned out a small army to chase
   me --- guns, nets, it was terrible.  Since then I've been reduced
   to eating mice, insects, even grass."  The fat one replies "Well,
   *I* hid near an IBM office and ate a manager a day.  And
   nobody even noticed!"

<LISP> [from "LISt Processing language", but mythically from "Lots
   of Irritating Superfluous Parentheses] n. The name of AI's mother
   tongue, a language based on the ideas of 1) variable-length lists
   and trees as fundamental data types, and 2) the interpretation of
   code as data and vice-versa.  Invented by John McCarthy at Stanford
   in the late 1950s, it is actually older than any other <HLL> still
   in use except FORTRAN.  Accordingly, it has undergone considerable
   adaptive radiation over the years; modern variants (of which Scheme
   is perhaps the most successful) are quite different in detail from
   the original LISP 1.5 at Stanford.  The hands-down favorite of
   hackers until the early 1980s, LISP now shares the throne with <C>.
   See <languages of choice>.

<literature, the> n. Used to answer a question that the hearer
   believes is <trivial>, as in "It's in the literature."  Oppose
   <Knuth>, which has no connotation of triviality.

<little-endian> adj. Describes a computer architecture in which,
   within a given 16- or 32-bit word, lower byte addresses have lower
   significance (the word is stored `little-end-first').  The PDP-11
   and VAX families of computers and Intel microprocessors and a lot
   of communications and networking hardware are little-endian.  See
   <big-endian>, <middle-endian>, <NUXI problem>.

<Live Free Or Die!> imp. 1. The state motto of New Hampshire.  2. A
   slogan associated with UNIX in the romantic days when UNIX
   aficionados saw themselves as a tiny, beleaguered underground
   tilting against the windmills of industry.  The "free" referred
   specifically to freedom from the <fascist> design phiolosophies and
   crufty misfeatures common on commercial operating systems.  Armando
   Stettner, one of the early UNIX developers, used to give out fake
   license plates bearing this motto under a large UNIX, all in New
   Hampshire colors of green and white.  These are now valued
   collector's items.

<livelock> n.  A situation in which some critical stage of a task is
   unable to finish because its clients perpetually create more work
   for it to do after they've been serviced but before it can clear.
   Differs from <deadlock> in that the process is not blocked or
   waiting for anything, but has a virtually infinite amount of work
   to do and accomplishes nothing.

<liveware> n. Synonym for <wetware> Less common.

<locked up> adj. Syn. for <hung>, <wedged>.

<logic bomb> n. Code surreptitiously inserted in an application or OS
   which causes it to perform some destructive or
   security-compromising activity whenever specified conditions are
   met.  Compare <back door>.

<logical> [from the technical term "logical device", wherein a
   physical device is referred to by an arbitrary name] adj.
   Understood to have a meaning not necessarily corresponding to
   reality.  E.g., if a person who has long held a certain post (e.g.,
   Les Earnest at SAIL) left and was replaced, the replacement would
   for a while be known as the "logical Les Earnest".  Compare
   <virtual>.  This use of <logical> is an extension from its
   technical use in computer science.  A program can be written to do
   input or output using a "logical device"; when the program is
   run, the user can specify which "physical" (actual) device to use
   for that logical device.  For example, a program might write all
   its error messages to a logical device called ERROR; the user can
   then specify whether logical device ERROR should be associated to
   the terminal, a disk file, or the <bit bucket> (to throw the error
   messages away).  Perhaps the word "logical" is used because even
   though a thing isn't the actual object in question, you can reason
   logically about the thing as if it were the actual object.

   At Stanford, "logical" compass directions denoted a coordinate
   system in which "logical north" is toward San Francisco,
   "logical west" is toward the ocean, etc., even though logical
   north varies between physical (true) north near San Francisco and
   physical west near San Jose.  (The best rule of thumb here is that
   El Camino Real by definition always runs logical north-and-south.)
   In giving directions, one might say, "To get to Rincon Tarasco
   restaurant, get onto El Camino Bignum going logical north."  Using
   the word "logical" helps to prevent the recipient from worrying
   about that the fact that the sun is setting almost directly in
   front of him.  The concept is perpetuated by North American
   highways which are almost, but not quite, consistently labelled
   with logical rather than physical directions.  A similar situation
   exists at MIT.  Route 128 (famous for the electronics industries
   that have grown up along it) is a three-quarters circle surrounding
   Boston at a radius of ten miles, terminating at the coastline at
   each end.  It would be most precise to describe the two directions
   along this highway as being "clockwise" and "counterclockwise",
   but the road signs all say "north" and "south", respectively.
   A hacker would describe these directions as "logical north" and
   "logical south", to indicate that they are conventional
   directions not corresponding to the usual convention for those
   words.  (If you went logical south along the entire length of route
   128, you would start out going northwest, curve around to the
   south, and finish headed due east!)

<loop through> v. To process each element of a list of things. "Hold
   on, I've got to loop through my paper mail."  Derives from the
   computer-language notion of an iterative loop; compare <cdr down>
   (which is less common among C and UNIX programmers).

<lord high fixer> [primarily British, prob. fr. Gilbert & Sullivan's
   "lord high executioner"] n. The person in an organization who
   knows the most about some aspect of a system.  See <wizard>.

<lose> [from MIT jargon] vi. 1. To fail.  A program loses when it
   encounters an exceptional condition or fails to work in the
   expected manner.  2. To be exceptionally unaesthetic.  3. Of
   people, to be obnoxious or unusually stupid (as opposed to
   ignorant).  4. <deserves to lose>: vi. Said of someone who
   willfully does the wrong thing; humorously, if one uses a feature
   known to be marginal.  What is meant is that one deserves the
   consequences of one's losing actions.  "Boy, anyone who tries to
   use <mess-dos> deserves to lose!" (ITS fans used to say this of
   UNIX; many still do) See also <screw>, <chomp>, <bagbiter>.  5.
   <lose> as a noun refers to something which is losing, especially in
   the phrases "That's a lose!" or "What a lose!".

<lose lose> interj. A reply or comment on an undesirable situation.
   "I accidentally deleted all my files!" "Lose lose."

<loser> n. An unexpectedly bad situation, program, programmer, or
   person.  Someone who habitually loses (even winners can lose
   occasionally).  Someone who knows not and knows not that he knows
   not.  emphatic forms are "real loser", "total loser", and
   "complete loser" (but not "moby loser", which would be a
   contradiction in terms). See <luser>.

<losing> adj. Said of anything which is or causes a <lose>.

<loss> n. Something (not a person) which loses; a situation in which
   something is losing.  Emphatic forms include "moby loss" "total
   loss", "complete loss".  Common interjections are "What a loss!"
   and "What a moby loss!"  Compare <lossage>.

<lossage> /los'@j/ n. The result of a bug or malfunction.  This is a
   collective noun.  "What a loss!" and "What lossage!" are nearly
   synonymous remarks.  The former is slightly more particular to the
   speaker's present circumstances while the latter implies a
   continuing lose of which the speaker is presently victim.  Thus
   (for example) a temporary hardware failure is a loss, but bugs in
   an important tool (like a compiler) are serious lossage.

<LPT> /lip'it/ [ITS] n. Line printer, of course.  Rare under UNIX,
   commoner in hackers with MS-DOS or CP/M background (the printer
   device is called LPT: on those systems, which like ITS were
   strongly influenced by early DEC conventions).

<lurker> n. One of the `silent majority' in a <USENET> or BBS
   newsgroup; one who posts occasionally or not at all but is known to
   read the group regularly.  Often in `the lurkers', the hypothetical
   audience for the group's <flamage>-emitting regulars.

<lunatic fringe> [IBM] n. Customers who can be relied upon to accept
   release 1 versions of software.

<luser> /loo'zr/ n.  A <user> who is probably also a <loser>.
   (<luser> and <loser> are pronounced identically.)  This word was
   coined about 1975 at MIT.  Under ITS, when you first walked up to a
   terminal at MIT and typed Control-Z to get the computer's
   attention, it prints out some status information, including how
   many people are already using the computer; it might print "14
   users", for example.  Someone thought it would be a great joke to
   patch the system to print "14 losers" instead.  There ensued a
   great controversy, as some of the users didn't particularly want to
   be called losers to their faces every time they used the computer.
   For a while several hackers struggled covertly, each changing the
   message behind the back of the others; any time you logged into the
   computer it was even money whether it would say "users" or
   "losers".  Finally, someone tried the compromise "lusers", and
   it stuck.  Later one of the ITS machines supported `luser' as a
   request-for-help command.  ITS died in early 1990; the usage lives
   on, however, and the term `luser' is often seen in program

                                {= M =}

<macdink> /mak'dink/ [from the Apple Macintosh, which is said to
   encourage such behavior] vt.  To make many incremental and
   unnecessary cosmetic changes to a program or file.  Frequently the
   subject of the macdinking would be better off without them.  Ex:
   "When I left at 11pm last night, he was still macdinking the
   slides for his presentation."

<Macintrash> /mak'in-trash/ The Apple Macintosh, as described by a
   hacker who doesn't appreciate being kept away from the *real
   computer* by the interface.  See also <WIMP environment>,
   <drool-proof paper>, <user friendly>.

<macro> /mak'ro/ n. A name (possibly followed by a formal <arg> list)
   which is equated to a text expression to which it is to be expanded
   (possibly with substitution of actual arguments) by a language
   translator.  This definition can be found in any technical
   dictionary; what those won't tell you is how the hackish
   connotations of the term have changed over time.  The term `macro'
   originated in early assemblers, which encouraged use of macros as a
   structuring and information-hiding device.  During the early 70s
   macro assemblers became ubiquitous and sometimes quite as powerful
   and expensive as HLLs, only to fall from favor as improving
   compiler technology marginalized assembler programming (see
   <languages of choice>). Nowadays the term is most often used in
   connection with the C preprocessor, LISP, or one of several
   special-purpose languages built around a macro-expansion facility
   (such as TeX or UNIX's nroff, troff and pic suite). Indeed, the
   meaning has drifted enough that the collective `macros' is now
   sometimes used for code in any special-purpose application-control
   language (whether or not the language is actually translated by
   text expansion) as well as other "expansions" such as the
   "keyboard macros" supported in some text editors (and PC TSR
   keyboard enhancers).

<machoflops> [pun on "megaflops", a coinage for "millions of
   floating-point operations per second"] n. Refers to artificially
   inflated performance figures often quoted by computer
   manufacturers.  Real applications are lucky to get half the quoted
   speed. Thus, machoflops are similar to EPA gas mileage estimates.
   See <benchmark>.

<macrology> /mak-ro'l@-jee/ n. Set of usually complex or crufty
   macros, e.g. as part of a large system written in LISP, <TECO> or
   (less commonly) assembler.  Sometimes studying the macrology of a
   system is not unlike archaeology, hence the sound-alike
   construction.  Prob. influenced by <ecology> and <theology>.

<macrotape> /ma'kro-tayp/ n. An industry standard reel of tape, as
   opposed to a <microtape>.

<magic> adj. 1. As yet unexplained, or too complicated to explain
   (compare <automagically> and Clarke's Third Law: "Any sufficiently
   advanced technology is indistinguishable from magic").  "TTY
   echoing is controlled by a large number of magic bits."  "This
   routine magically computes the parity of an eight-bit byte in three
   instructions." 2.  Characteristic of something that works but no
   one really understands why.  3. [Stanford] A feature not generally
   publicized which allows something otherwise impossible, or a
   feature formerly in that category but now unveiled.  Example: The
   keyboard commands which override the screen-hiding features.

<magic cookie> [UNIX] n. 1. Something passed between routines or
   programs that enables the receiver to perform some <obscure>
   operation; a capability ticket or opaque identifier.  Especially
   used of small data objects which contain data encoded in a strange
   or intrinsically machine-dependent way.  For example, on non-UNIX
   OSs with a non-byte-stream model of files, the result of `ftell(3)'
   may be a `magic cookie' rather than a byte offset; it can be passed
   to `fseek(3)' but not operated on in any meaningful way.  2. An
   in-band code for changing graphic rendition (i.e. inverse video or
   underlining) or performing other control functions.  Some older
   terminals would leave a blank on the screen corresponding to
   mode-change cookies; this was also called a <glitch>.  See also

<magic number> [UNIX/C] n. 1. Special data located at the beginning of
   a binary data file to indicate its type to a utility.  Under UNIX
   the system and various applications programs (especially the
   linker) distinguish between types of executable by looking for a
   magic number. 2. In source code, some non-obvious constant whose
   value is significant to the operation of a program and is inserted
   inconspicuously in line, rather than expanded in by a symbol set by
   a commented #define.  Magic numbers in this sense are bad style.

<magic smoke> n. A notional substance trapped inside IC packages that
   enables them to function (also called "blue smoke"). Its
   existence is demonstrated by what happens when a chip burns up ---
   the magic smoke gets let out, so it doesn't work any more.  See
   <smoke test>.

<management> n. 1. Corporate power elites distinguished primarily by
   their distance from actual productive work and chronic failure to
   manage (see also <suit>).  Spoken derisively, as in
   "*Management* decided that..." 2. Mythically, a vast
   bureaucracy responsible for all the world's minor irritations.
   Hackers' satirical public notices are often signed "The Mgmt".

<mangle> vt. Used similarly to <mung> or <scribble>, but more violent
   in its connotations; something that is mangled has been
   irreversibly and totally trashed.

<mango> [orig. in-house slang at Symbolics] n.  A manager.  See also
   <devo> and <doco>.

<marginal> adj. 1. Extremely small.  "A marginal increase in core can
   decrease <GC> time drastically."  In everyday terms, this means
   that it's a lot easier to clean off your desk if you have a spare
   place to put some of the junk while you sort through it. 2. Of
   extremely small merit.  "This proposed new feature seems rather
   marginal to me."  3. Of extremely small probability of winning.
   "The power supply was rather marginal anyway; no wonder it
   fried."  4.  <marginally>: adv.  Slightly.  "The ravs here are
   only marginally better than at Small Eating Place."  See <epsilon>.
   4. <marginal hacks>: n. Margaret Jacks Hall, a building into which
   the Stanford AI Lab was moved near the beginning of the '80s.

<marketroid> /mar'k@-troyd/ alt. <marketing slime>, <marketing
   droid>, <marketeer> n.  Member of a company's marketing department,
   esp.  one who promises users that the next version of a product
   will have features which are unplanned, extremely difficult to
   implement, and/or violate the laws of physics; and/or one who
   describes existing features (and misfeatures) in ebullient,
   buzzword-laden adspeak.  Derogatory.  Used by techies.

<martian> n. A packet sent on a TCP/IP network with a source address
   of the test loopback interface (  As in "The domain
   server is getting lots of packets from Mars.  Does that gateway
   have a Martian filter?"

<massage> vt. Vague term used to describe `smooth' transformations of
   a data set into a more useful form, esp.  transformations which do
   not lose information.  Connotes less pain than <munch> or <crunch>.
   "He wrote a program that massages X bitmap files into GIF
   format."  Compare <slurp>.

<meatware> n. Synonym for <wetware>.  Less common.

<meg> /meg/ n. A megabyte; 1024K.

<mega-> /me'ga/ pref. See <kilo>.

<megapenny> /meg'a-pen'ee/ n. $10,000 (1 cent * 10e6). Used
   semi-humorously as a unit in comparing computer cost/performance

<MEGO> /mego/ or /meego/ [My Eyes Glaze Over, often Mine Eyes Glazeth
   Over, attributed to the futurologist Herman Kahn] Also "MEGO
   factor".  1.  Handwaving intended to confuse the listener and
   hopefully induce agreement because the listener does not want to
   admit to not understanding what is going on.  MEGO is usually
   directed at senior management by engineers and contains a high
   proportion of <TLA>s. 2. excl. An appropriate response to MEGO

<meltdown, network> n. A state of complete network overload; the
   network equivalent of <thrash>ing.  See also <broadcast storm>.

<meme> /meem/ [coined on analogy with `gene' by Richard Dawkins] n. An
   idea considered as a <replicator>. Used esp. in the prase `meme
   complex' denoting a group of mutually supporting memes which form
   an organized belief system, such as a religion.  This dictionary is
   a vector of the "hacker subculture" meme complex; each entry
   might be considered a meme.  However, "meme" is often misused to
   mean "meme complex". Use of the term connotes acceptance of the
   idea that in humans (and presumably other tool-and language-using
   sophonts) cultural evolution by selection of adaptive ideas has
   superseded biological evolution by selection of hereditary traits.
   Hackers find this idea congenial for tolerably obvious reasons.

<meme plague> n. The spread of a successful but pernicious <meme>,
   esp.  one which `parasitizes' the victims into giving their all to
   propagate it.  Astrology, BASIC, and the other guy's religion are
   often considered to be examples.  This usage is given point by the
   historical fact that `joiner' ideologies like Naziism or various
   forms of millenarian Christianity have exhibited plague-like cycles
   of exponential growth followed by collapse to small `reservoir'

<memetics> /me-me-tiks/ [from <meme>] The study of memes.  As of 1990,
   this is still an extremely informal and speculative endeavor,
   though the first steps towards at least statistical rigor have been
   made by H. Keith Henson and others.  Memetics is a popular topic
   among hackers, who like to see themselves as the architects of the
   new information ecologies in which memes live and replicate.

<memory leak> [C/UNIX programmers] n. An error in a program's
   dynamic-store allocation logic that causes it to fail to reclaim
   discarded memory, leading to attempted hogging of main store and
   eventual collapse due to memory exhaustion.  Also (esp. at CMU)
   called <core leak>.  See <aliasing bug>, <fandango on core>, <smash
   the stack>, <precedence lossage>, <overrun screw>, <leaky heap>.

<menuitis> /men`yoo-i'tis/ n. Notional disease suffered by software
   with an obsessively simple-minded menu interface and no escape.
   Hackers find this intensely irritating and much prefer the
   flexibility of command-line or language-style interfaces,
   especially those customizable via macros or a special-purpose
   language in which one can encode useful hacks.  See
   <user-obsequious>, <drool-proof paper>, <WIMP environment>.

<mess-dos> /mes-dos/ [UNIX hackers] n. Derisory term for MS-DOS. Often
   followed by the ritual expurgation "Just Say No!". See MS-DOS.
   Most hackers (even many MS-DOS hackers) loathe MS-DOS for its
   single-tasking nature, its limits on application size, its nasty
   primitive interface, and its ties to IBMness (see <fear and
   loathing>). Also "mess-loss", "messy-dos", "mess-dog"
   "mess-loss" "mess-dross" and various combinations thereof.

<meta> /meta@/ or /mayt'@/ [from analytic philosophy] adj. One level
   of description up.  Thus, a meta-syntactic variable is a variable
   in notation used to describe syntax and meta-language is language
   used to describe language.  This is difficult to explain out of
   context, but much hacker humor turns on deliberate confusion
   between meta-levels.  See <HUMOR, HACKER>.

<meta bit> /meta@ bit/ or /mayt'@ bit/ n. Bit 8 of an 8-bit
   character, on in values 128-255. Also called <high bit> or <alt
   bit>.  Some terminals and consoles (especially those designed for
   LISP traditions) have a META-shift key.  Others (including,
   mirabile dictu, keyboards on IBM PC-class machines) have an ALT
   key.  See also <bucky bits>.

<microfloppies> n. 3-1/2 inch floppies, as opposed to 5-1/4 <vanilla>
   or mini-floppies and the now-obsolescent 8-inch variety.  This term
   may be headed for obsolescence as 5-1/4 inchers pass out of use,
   only to be revived if anybody floats a sub-3-inch floppy standard.
   See <stiffy>.

<microtape> n. Occasionally used to mean a DECtape, as opposed to a
   <macrotape>.  A DECtape is a small reel of magnetic tape about four
   inches in diameter and an inch deep.  Unlike normal drivers for
   standard magnetic tapes, microtape drivers allow "random access"
   to the data.  In their heyday they were used in pretty much the
   same ways one would now use a floppy disk: as a small, portable way
   to save and transport files and programs.  Apparently the term
   "microtape" was actually the official term used within DEC for
   these tapes until someone consed up the word "DECtape", which of
   course sounded sexier to the <marketroid> types.

<middle-endian> adj. Not <big-endian> or <little-endian>.  Used of
   byte orders like 3-4-1-2 occasionally found in the packed-decimal
   formats of minicomputer manufacturers who shall remain nameless.

<millilampson> /mil'i-lamp-sn/ n.  How fast people can talk.  Most
   people run about 200 millilampsons.  Butler Lampson (a CS theorist
   and systems implementor highly regarded among hackers) goes at
   1000.  A few people speak faster.

<MIPS> /mips/ [acronym] 1. A measure of computing speed; formally,
   "Millions of Instructions Per Second"; often rendered by hackers
   as "Meaningless Indication of Processor Speed". This joke
   expresses a nearly universal attitude about the value of
   <benchmark> claims, said attitude being one of the great cultural
   divides between hackers and <marketroid>s.  2. The corporate name
   of a RISC-chip maker; among other things, they supplied silicon for
   the DEC 3100 workstation series.

<misbug> [mit] n. An unintended property of a program that turns out
   to be useful; something that should have been a <bug> but turns out
   to be a <feature>.  Usage: rare.

<misfeature> /mis-fee'chr/ n. A feature which eventually screws
   someone, possibly because it is not adequate for a new situation
   which has evolved.  It is not the same as a bug because fixing it
   involves a gross philosophical change to the structure of the
   system involved.  A misfeature is different from a simple
   unforeseen side effect; the term implies that the misfeature was
   actually carefully planned to be that way, but future consequences
   or circumstances just weren't predicted accurately.  This is
   different from just not having thought ahead about it at all.
   Often a former feature becomes a misfeature because a tradeoff was
   made whose parameters subsequently changed (possibly only in the
   judgment of the implementors).  "Well, yeah, it's kind of a
   misfeature that file names are limited to six characters, but the
   original implementors wanted to save directory space and we're
   stuck with it for now."

<Missed'em-five> n. Pejorative hackerism for AT&T System V UNIX,
   generally used by <BSD> partisans in a bigoted mood.  See <software
   bloat>, <Berzerkely>.

<moby> [seems to have been in use among model railroad fans years ago.
   Derived from Melville's "Moby Dick" (some say from "Moby
   Pickle").]  1. adj. Large, immense, complex, impressive.  "A
   Saturn V rocket is a truly moby frob."  "Some MIT undergrads
   pulled off a moby hack at the Harvard-Yale game." (see Appendix
   A).  2. n. obs.  The maximum address space of a machine (see
   below).  For a 68000 or VAX or most modern 32-bit architectures, it
   is 4294967296 8-bit bytes.  3.  A title of address (never of
   third-person reference), usually used to show admiration, respect,
   and/or friendliness to a competent hacker.  "Greetings, moby Dave.
   How's that address-book thing for the Mac going?"  4.  adj. In
   backgammon, doubles on the dice, as in "moby sixes", "moby
   ones", etc.  Compare this with <bignum> (sense #2): double sixes
   are both bignums and moby sixes, but moby ones are not bignums (the
   use of term "moby" to describe double ones is sarcastic).  <moby
   foo>, <moby win>, <moby loss>: standard emphatic forms.  <foby
   moo>: a spoonerism due to Greenblatt.

   This term entered hackerdom with the Fabritek 256K moby memory of
   the MIT-AI machine. Thus, a moby is classically, 256K 36-bit words,
   the size of a PDP-10 moby (it has two).  Back when address
   registers were narrow, the term was more generally useful; because
   when a computer had virtual memory mapping it might actually
   have more physical memory attached to it than any one program could
   access directly.  One could then say "This computer has six
   mobies" to mean that the ratio of physical memory to address space
   is six, without having to say specifically how much memory there
   actually is.  That in turn implied that the computer could
   timeshare six "full-sized" programs without having to swap
   programs between memory and disk.

   Nowadays the low cost of processor logic means that registers are
   typically wider than the most memory you can cram onto a machine,
   so most systems have much *less* than 1 theoretical `native'
   moby of core.  Also, more modern memory-management techniques make
   the `moby count' less significant.  However, there is one series of
   popular chips for which the term could stand to be revived -- the
   Intel 8088 and 80286 with their incredibly brain-damaged
   segmented-memory design.  On these, a `moby' would be the
   1-megabyte address span of a paragraph-plus-offset pair.

<mode> n. A general state, usually used with an adjective describing
   the state.  Use of the word "mode" rather than "state" implies
   that the state is extended over time, and probably also that some
   activity characteristic of that state is being carried out. "No
   time to hack; I'm in thesis mode."  Usage: in its jargon sense,
   "mode" is most often said of people, though it is sometimes
   applied to programs and inanimate objects. "The E editor normally
   uses a display terminal, but if you're on a TTY it will switch to
   non-display mode."  This term is normally used in a technical sense
   to describe the state of a program.  Extended usage --- for
   example, to describe people --- is definitely slang.  In
   particular, see <hack mode>, <day mode>, <night mode>, <demo mode>,
   <fireworks mode> and <yoyo mode>; also <talk mode>.

   One also often hears the verbs "enable" and "disable" used in
   connection with slang modes.  Thus, for example, a sillier way of
   saying "I'm going to crash" is "I'm going to enable crash mode
   now."  One might also hear a request to "disable flame mode,

<modulo> /mod'yuh-low/ prep. Except for.  From mathematical
   terminology: one can consider saying that 4=22 "except for the
   9's" (4=22 mod 9) (the precise meaning is a bit more complicated,
   but that's the idea).  "Well, LISP seems to work okay now, modulo
   that <GC> bug."  "I feel fine today modulo a slight headache."

<monkey up> vt. To hack together hardware for a particular task,
   especially a one-shot job.  Connotes an extremely <crufty> and
   consciously temporary solution.

<monstrosity> 1. n. A ridiculously <elephantine> program or system,
   esp.  one which is buggy or only marginally functional.  2.  The
   quality of being monstrous (see `Peculiar nouns' in the discussion
   of jargonification).  See also <baroque>.

<Moore's Law> /morz law/ n. The observation that the logic density of
   silicon integrated circuits has closely followed the curve (bits
   per inch ^ 2) = 2 ^ (n - 1962); that is, the amount of
   information storable in one square inch of silicon has roughly
   doubled yearly every year since the technology was invented.

<moria> /mor'i-ah/ n. Together with <nethack> and <rogue>, one of the
   large PD Dungeons-and-Dragons simulation games, available for a
   wide range of machines and operationg systems.  Extremely addictive
   and a major consumer of time better used for hacking.

<MOTAS> /moh-tahs/ [USENET, Member Of The Appropriate Sex] n. A
   potential or (less often) actual sex partner.  See <MOTOS>,
   <MOTSS>, <S.O>.

<MOTOS> /moh-tohs/ [from the 1970 census forms via USENET, Member Of
   The Opposite Sex] n. A potential or (less often) actual sex
   partner.  See <MOTAS>, <MOTSS>, <S.O.> Less common than <MOTSS> or
   <MOTAS>, which has largely displaced it.

<MOTSS> /motss/ [from the 1970 census forms via USENET, Member Of The
   Same Sex] n. Esp. one considered as a possible sexual partner, e.g.
   by a gay or lesbian.  The gay-issues newsgroup on USENET is called
   soc.motss.  See <MOTOS> and <MOTAS>, which derive from it.  Also
   see <S.O.>.

<mount> vt. 1. To attach a removable physical storage volume to a
   machine.  In elder days and on mainframes this verb was used almost
   exclusively of tapes; nowadays it is more likely to refer to a disk
   or disk pack. 2.  By extension, to attach any removable device such
   as a sensor, robot arm, or <meatware> subsystem (see Appendix A).
   3.  [UNIX] To make a <logical> volume of some sort available for
   use.  The volume in question may or may not be removable and may be
   just one partition of a physical device.

<mouse ahead> vi. To manipulate a computer's pointing device (almost
   always a mouse in this usage, but not necessarily) and its
   selection or command buttons before a computer program is ready to
   accept such input, in anticipation of the program accepting the
   input.  Handling this properly is rare, but it can help make a
   <user friendly> program usable by real users, assuming they are
   familiar with the behavior of the user interface.  Point-and-click
   analog of "type ahead".

<mouse around> vi. To explore public portions of a large system, esp.
   a network such as Internet via <FTP> or <TELNET>, looking for
   interesting stuff to <snarf>.

<mouse elbow> n.  A tennis-elbow-like fatigue syndrome resulting from
   excessive use of a <WIMP environment>.

<mouso> /mow'so/ n. [by analogy with `typo'] An error in mouse usage
   resulting in an inappropriate selection or graphic garbage on the
   screen.  Compare <thinko>.

<MS-DOS> /em-es-dos/ [MicroSoft Disk Operating System] n. A <clone> of
   <CP/M> for the 8088 crufted together in six weeks by hacker Tim
   Paterson, who is said to have regretted it ever since.  Numerous
   features including vaguely UNIX-like but rather broken support for
   subdirectories, I/O redirection, and pipelines were hacked in in
   2.0 and subsequent versions; as a result, there are two
   incompatible versions of many system calls, and MS-DOS programmers
   can never agree on basic things like what to use as an option
   switch or whether to be case-sensitive.  Now the
   highest-unit-volume OS in history.  Often known simply as DOS,
   which annoys people familiar with other similarly-abbreviated
   operating systems.  See <mess-dos>, <ill-behaved>.

<MUD> [acronym for "Multi-user Interactive Dungeons"] n. A class of
   <virtual reality> experiments accessible via <Internet>.  These are
   real-time chat forums with structure; they have multiple
   `locations' like an adventure game and may include traps, puzzles,
   magic, a simple economic system, and the capability for characters
   to build more structure onto the database that represents the
   existing world.  However, there is no notion that corresponds to
   `winning' an adventure game, and interaction is primarily social.
   The acronym MUD is often lower-cased and/or verbed; thus, one may
   speak of "going mudding", etc.

<multician> /muhl-ti'sh@n/ [coined at Honeywell, c.1970] n.
   Competent user of <Multics>.

<Multics> /muhl'tiks/ n. [from "MULTiplexed Information and Computing
   Service"] An early (late 1960s) timesharing operating system
   co-designed by a consortium including MIT, GE and Bell
   Laboratories, very innovative for its time (among other things, it
   introduced the idea of treating all devices uniformly as special
   files). All the members but GE eventually pulled out after
   determining that <second-system effect> had bloated MULTICS to the
   point of practical unusability (the `lean' predecessor in question
   is said to have been <CTSS>).  Honeywell commercialized Multics
   after buying out GE's computer group, but it was never very
   successful (among other things, one was required to enter a
   password to log out).  One of the developers left in the lurch by
   the project's breakup was Ken Thompson, a circumstance which led
   directly to the birth of <UNIX>. For this and other reasons
   aspects of the Multics design remain a topic of occasional debate
   among hackers.  See also <brain-damage>.

<mumblage> /mum'bl@j/ n. The topic of one's mumbling (see <mumble>).
   "All that mumblage" is used like "all that stuff" when it is
   not quite clear what it is or how it works, or like "all that
   crap" when "mumble" is being used as an implicit replacement for

<mumble> interj. 1. Said when the correct response is either too
   complicated to enunciate or the speaker has not thought it out.
   Often prefaces a longer answer, or indicates a general reluctance
   to get into a big long discussion.  "Don't you think that we could
   improve LISP performance by using a hybrid reference-count
   transaction garbage collector, if the cache is big enough and there
   are some extra cache bits for the microcode to use?"  "Well,
   mumble... I'll have to think about it."  2. Sometimes used as an
   expression of disagreement.  "I think we should buy a <VAX>."
   "Mumble!"  Common variant: <mumble frotz>. 3. Yet another
   metasyntactic variable, like <foo>.

<munch> [often confused with `mung', q.v.] vt. To transform
   information in a serial fashion, often requiring large amounts of
   computation.  To trace down a data structure.  Related to <crunch>
   and nearly synonymous with <grovel>, but connotes less pain.

<munching squares> n. A <display hack> dating back to the PDP-1, which
   employs a trivial computation (involving XOR'ing of x-y display
   coordinates --- see <HAKMEM> items 146-148) to produce an
   impressive display of moving, growing, and shrinking squares.  The
   hack usually has a parameter (usually taken from toggle switches)
   which when well-chosen can produce amazing effects.  Some of these,
   (re)discovered recently on the LISP machine, have been christened
   <munching triangles>, <munching w's>, and <munching mazes>.  More
   generally, suppose a graphics program produces an impressive and
   ever-changing display of some basic form foo on a display terminal,
   and does it using a relatively simple program; then the program (or
   the resulting display) is likely to be referred to as "munching
   foos" (this is a good example of the use of the word <foo> as a
   metasyntactic variable).

<munchkin> /muhnch'kin/ n. A teenage-or-younger micro enthusiast
   bashing BASIC or something else equally constricted.  A term of
   mild derision --- munchkins are annoying but some grow up to be
   hackers after passing through a <larval stage>.  The term <urchin>
   is also used.  See also <bitty box>.

<mundane> [from SF fandom] n.  1.  A person who is not in science
   fiction fandom. 2.  A person who is not in the computer industry.
   In this sense, most often an adjectival modifier as in "in my
   mundane life..."

<mung> /muhng/ alt. `munge' /muhnj/ [in 1960 at MIT, "Mash Until No
   Good"; sometime after that the derivation from the recursive
   acronym "Mung Until No Good" became standard] vt.  1.  To make
   changes to a file, often large-scale, usually irrevocable.
   Occasionally accidental.  See <BLT>.  2. To destroy, usually
   accidentally, occasionally maliciously.  The system only mungs
   things maliciously; this ia a consequence of Murphy's Law.  See
   <scribble>, <mangle>, <trash>.  Reports from <USENET> suggest that
   the pronunciation /muhnj/ is now usual in speech, but the spelling
   `mung' is still common in program comments. 3. The kind of beans of
   which the sprouts are used in Chinese food.  (That's their real
   name!  Mung beans!  Really!)

<MUSIC> n. A common extracurricular interest of hackers (compare
   <SCIENCE-FICTION FANDOM>, <ORIENTAL FOOD>; see also <filk>).  It is
   widely believed among hackers that there is a substantial
   correlation between whatever mysterious traits underlie hacking
   ability (on the one hand) and musical talent and sensitivity (on
   the other). It is certainly the case that hackers, as a rule, like
   music and often develop musical appreciation in unusual and
   interesting directions.  Folk music is very big in hacker circles;
   so is the sort of elaborate instrumental jazz/rock that used to be
   called `progressive' and isn't recorded much any more.  Also, the
   hacker's musical range tends to be wide; many can listen with equal
   appreciation to (say) Talking Heads, Yes, Spirogyra, Scott Joplin,
   King Sunny Ade, The Pretenders, or one of Bach's Brandenburg
   Concerti.  It is also apparently true that hackerdom includes a
   much higher concentration of talented amateur musicians than one
   would expect from a similar-sized control group of <mundane> types.

<mutter> vt. To quietly enter a command not meant for the ears of
   ordinary mortals.  Frequently in "mutter an <incantation>".

                                {= N =}

<N> /en/ adj. 1. Some large and indeterminate number of objects;
   "There were N bugs in that crock!"; also used in its original
   sense of a variable name.  2. An arbitrarily large (and perhaps
   infinite) number; "This crock has N bugs, as N goes to infinity".
   3. A variable whose value is specified by the current context.  For
   example, when ordering a meal at a restaurant N may be understood
   to mean however many people there are at the table.  From the
   remark "We'd like to order N wonton soups and a family dinner for
   N-1." you can deduce that one person at the table wants to eat
   only soup, even though you don't know how many people there are.  A
   silly riddle: "How many computers does it take to shift the bits
   in a register?  N+1: N to hold all the bits still, and one to shove
   the register over." 4. NTH: adj. The ordinal counterpart of N.
   "Now for the Nth and last time..."  In the specific context
   "Nth-year grad student", N is generally assumed to be at least 4,
   and is usually 5 or more.  See also <random numbers>,

<nailed to the wall> [like a trophy] adj. Said of a bug finally
   eliminated after protracted and even heroic effort.

<NAK> [from the ASCII mnemonic for 0010101] interj.  1. On-line joke
   answer to ACK? (see <ACK>) -- "I'm not here". 2. On line answer
   to a request for chat -- "I'm not available".  3. Used to
   politely interrupt someone to tell them you don't understand their
   point or that they have suddenly stopped making sense.  See <ACK>,
   sense #3.  "And then, after we recode the project in COBOL..."
   "Nak Nak Nak!  I thought I heard you say COBOL!"

<nanoacre> /nan'o-ay-kr/ n. An areal unit (about 2mm.sq.) of
   "real-estate" on a VLSI chip.  The term derives its amusement
   value from the fact that VLSI nanoacres have costs in the same
   range as real acres once one figures in design and
   fabrication-setup costs.

<nanobot> /nan'oh-bot/ n. A robot of microscopic proportions,
   presumably built by means of <nanotechnology>.  As yet, only used
   informally (and speculatively!). Also sometimes called a

<nanocomputer> /nan'oh-k@m-pyoo-tr/ n. A computer whose switching
   elements are molecular in size.  Designs for mechanical
   nanocomputers which use single-molecule sliding rods for their
   logic have been proposed.  The controller for a <nanobot> would be
   a nanocomputer.

<nanotechnology> /nan'-oh-tek-naw`l@-ji/ n. A hypothetical
   fabrication technology in which objects are designed and built with
   the individual specification and placement of each separate atom.
   The first unequivocal nano-fabrication experiments are taking place
   now (1990), for example with the deposition of individual xenon
   atoms on a nickel substrate to spell the logo of a certain very
   large computer company by two of its physicists.  Nanotechnology
   has been a hot topic in the hacker subculture ever since the term
   was coined by K. Eric Drexler in his book `Engines of Creation',
   where he predicted that nanotechnology could give rise to
   replicating assemblers, permitting an exponential growth of
   productivity and personal wealth.  See also <blue goo>, <gray goo>,

<nastygram> n. 1. A protocol packet or item of email (the latter is
   also called a `letterbomb') that takes advantage of misfeatures or
   security holes on the target system to do untoward things. 2.
   Disapproving mail, esp. from a net.god, pursuant to a violation of
   <netiquette>.  Compare <shitogram>.  3. (deprecated) An error reply
   by mail from a <daemon>; in particular, a <bounce message>.

<neophilia> /nee-oh-fil'-ee-uh/ n. The trait of being excited and
   pleased by novelty.  Common trait of most hackers, SF fans, and
   members of several other connected "leading-edge" subcultures
   including the pro-technology "Whole-Earth" wing of the ecology
   movement, space activists, theater people, the membership of MENSA,
   and the <Discordian>/neo-pagan underground.  All these groups
   overlap heavily and (where evidence is available) seem to share
   characteristic hacker tropisms for SF, <MUSIC> and <ORIENTAL FOOD>.

<nethack> /net'hak/ n. See <hack>, sense #12.

<netiquette> /net'ee-ket, net'i-ket/ [portmanteau "network
   ettiquette"] n. Conventions of politeness recognized on <USENET>,
   such as: avoidance of cross-posting to inappropriate groups, or
   refraining from commercial pluggery on the net.

<neep-neep> /neep neep/ [onomatopoeic, from New York SF fandom] n. One
   who is fascinated by computers.  More general than <hacker>, as it
   need not imply more skill than is required to boot games on a PC.
   The gerund <neep-neeping> applies specifically to the long
   conversations about computers that tend to develop in the corners
   at most SF-convention parties.  Fandom has a related proverb to the
   effect that "Hacking is a conversational black hole!"

<net.*> /net dot/ pref. [USENET] Prefix used to describe people and
   events related to USENET.  From the time before the <Great
   Renaming>, when all non-local newsgroups had names beginning
   "net.".  Includes net.god(s) (q.v.), net.goddesses (various
   charismatic women with circles of on-line admirers), net.lurkers,
   (see <lurker>), net.parties (a synonym for <boink> sense #2 (q.v.))
   and many similar constructs.  See also <net.police>.

<net.god> (net god) n. Used to refer to anyone who satisfies some
   combination of the following conditions: has been visible on USENET
   for more than five years, ran one of the original backbone sites,
   moderated an important newsgroup, wrote news software, or knows
   Gene, Mark, Rick, Mel, Henry, Chuq, and Greg personally.  See

<net.police> n.  Those USENET readers who feel it is their
   responsibility to pounce on and <flame> any posting which they
   regard as offensive, or in violation of their understanding of
   <netiquette>.  Generally used sarcastically or pejoratively.  Also
   spelled `net police'. See also <net.>, <code police>.

<network address> n. As used by hackers, means an address on <the
   network> (almost always a <bang path> or <Internet address>). An
   essential to be taken seriously by hackers; in particular, persons
   or organizations claiming to understand, work with, sell to, or
   recruit from among hackers that *don't* display net addresses
   are quietly presumed to be clueless poseurs and mentally flushed
   (see <flush>, sense #3).  Hackers often put their net addresses on
   their business cards and wear them prominently in contexts where
   they expect to meet other hackers face-to-face (see also
   <SCIENCE-FICTION FANDOM>).  This is mostly functional, but is also
   a connotative signal that one identifies with hackerdom (like lodge
   pins among Masons or tie-died T-shirts among Grateful Dead fans).
   Net addresses are often used in email text as a more concise
   substitute for personal names; indeed, hackers may come to know
   each other quite well by network names without ever learning each
   others' `legal' monikers.  See also <sitename>.

<network, the> n. 1. The union of all the major academic and
   noncommercial/hacker-oriented networks such as Internet, the old
   ARPANET, NSFNet, BITNET and the virtual UUCP and <USENET>
   "networks", plus the corporate in-house networks that gate to
   them.  A site is generally considered `on the network' if it can be
   reached through some combination of Internet-style (@-sign) and
   UUCP (bang-path) addresses.  See <bang path>, <Internet address>,
   <network address>. 2. A fictional conspiracy of libertarian
   hacker-subversives and anti-authoritarian monkeywrenchers described
   in Robert Anton Wilson's novel `Schrodinger's Cat', to which many
   hackers have subsequently decided they belong (this is an example
   of <ha ha only serious>).

<New Testament> n. [C programmers] The second edition of K&R's "The C
   Programming Language" (Prentice-Hall 1988, ISBN 0-13-110362-8),
   describing ANSI Standard C. See <K&R>.

<newbie> /n[y]oo'bee/ n. [orig. fr. British military & public-school
   slang contraction of "new boy"] A USENET neophyte.  This term
   originated in the <newsgroup> "talk.bizarre" but is now in wide
   use.  Criteria for being considered a newbie vary wildly; a person
   can be called a newbie in one newsgroup while remaining a respected
   participant in another.  The label "newbie" is sometimes applied
   as a serious insult, to a person who has been around USENET for a
   long time, but who carefully hides all evidence of having a clue.
   See <biff>.

<newgrp wars> /n[y]oo'grp wohrz/ [USENET] n. Salvos of dueling
   `newgrp' and `rmgroup' messages sometimes exchanged by persons on
   opposite sides of a dispute over whether a <newsgroup> should be
   created netwide.  These usually settle out within a week or two as
   it becomes clear whether the group has a natural constituency
   (usually, it doesn't). At times, especially in the completely
   anarchic `alt' hierarchy, the names of newsgroups themselves become
   a form of comment or humor; cf. the spinoff of
   alt.swedish.chef.bork.bork.bork from in early 1990,
   or any number of specialized abuse groups named after particularly
   notorious <flamer>s.

<newline> /n[y]oo'lien/ n. 1. [UNIX] The ASCII LF character (0001010),
   used under <UNIX> as a text line terminator.  A Bell-Labs-ism
   rather than a Berkeleyism; interestingly (and unusually for UNIX
   slang) it is said originally to have been an IBM usage (though it
   appears in the ASCII standard).  2. More generally, any magic
   character sequence or operation (like Pascal's writeln() function)
   required to terminate a text record.  See <crlf>, <terpri>.

<newsfroup> /n[y]oos'froop/ [USENET] n. Silly written-only synonym for
   <newsgroup>, originated as a typo but now in regular use on
   USENET'S talk.bizarre and other not-real-tightly-wrapped groups.

<newsgroup> [USENET] n. One of USENET's large collection of topic
   groups.  Among the best-known are comp.lang.c (the C-language
   forum), comp.1.wizards (for UNIX wizards), rec.arts.sf-lovers
   (for science-fiction fans) and talk.politics.misc (miscellaneous
   political discussions and <flamage>).

<nickle> n. A <nybble> + 1; 5 bits.  Reported among developers for
   Mattel's GI 1600 (the Intellivision games processor), a chip with
   16-bit-wide RAM but 10-bit-wide ROM.  See also <deckle>.

<night mode> n. See <phase> (of people).

<nil> [from LISP terminology for "false"] No.  Usage: used in reply
   to a question, particularly one asked using the "-P" convention.
   See T.

<NMI> n. Non-Maskable Interrupt.  See <priority interrupt>.

<noddy> [Great Britain; from the children's books] adj. Small and
   unuseful, but demonstrating a point. Noddy programs are often
   written when learning a new language or system. The archetypal
   noddy program is <hello world>.  Noddy code may be used to
   demonstrate a feature or bug of a compiler, but would not be used
   in a real program. May be used of real hardware or software to
   imply that it isn't worth using.  "This editor's a bit noddy."

<non-optimal (or sub-optimal) solution> n. An astoundingly stupid way
   to do something.  This term is generally used in deadpan sarcasm,
   as its impact is greatest when the person speaking looks completely
   serious.  Compare <stunning>.  See also <Bad Thing>.

<nonlinear> adj. [scientific computation] Behaving in an erratic and
   unpredictable fashion.  When used to describe the behavior of a
   machine or program, it suggests that said machine or program is
   being forced to run far outside of design specifications.  This
   behavior may be induced by unreasonable inputs, or may be triggered
   when a more mundane bug sends the computation far away from its
   expected course.  When describing the behavior of a person,
   suggests a tantrum or a <flame>.  "When you talk to Bob, don't
   mention the drug problem or he'll go nonlinear for hours."

<nontrivial> adj. Requiring real thought or significant computing
   power.  Often used as an understated way of saying that a problem
   is quite difficult.  See <trivial>, <uninteresting>, <interesting>.

<no-op> /noh-op/ alt. NOP (nop) [no operation] n. 1. A machine
   instruction that does nothing (sometimes used in assembler-level
   programming as filler for data areas).  2. A person who contributes
   nothing to a project, or has nothing going on upstairs, or both.
   As in "he's a no-op.". 3. Any operation or sequence of operations
   with no effect, such as circling the block without finding a
   parking space, or putting money into a vending machine and having
   it fall immediately into the coin-return box, or asking someone for
   help and being told to go away.  "Oh well, that was a no-op."

<NP-> /en pee/ pref. Extremely.  Used to modify adjectives describing
   a level or quality of difficulty.  "Getting this algorithm to
   perform correctly in every case is NP-annoying."  This is
   generalized from the computer science terms "NP-hard" and
   "NP-complete".  NP is the set of Nondeterministic-Polynomial
   algorithms, those which can be completed by a nondeterministic
   finite state machine in an amount of time that is a polynomial
   function of the size of the input.

<nuke> vt. 1. To intentionally delete the entire contents of a given
   directory or storage volume. "On UNIX, rm -r /usr will nuke
   everything in the usr filesystem."  Never used for accidental
   deletion.  Oppose <blow away>. 2. Syn. for <dike>, applied to
   smaller things such as files, features or code sections. 3. Used of
   processes as well as files; frequently an alias for "kill -9" on

<null device> n. A <logical> input/output device connected to the <bit
   bucket>; when you write to it nothing happens, when you reaad from
   it you get a zero-length record full of nothing.  Useful for
   discarding unwanted output or using interactive programs in a
   non-interactive way.  See </dev/null>.

<numbers> [scientific computation] n. Results of a computation that may
   not be physically significant, but at least indicate that the
   program is running.  May be used to placate management, grant
   sponsors, etc.  <Making numbers> means running a program because
   output---any output, not necessarily meaningful output---is needed
   as a demonstration of progress.  See <pretty pictures>.

<NUXI problem> /nuk'see pro'blm, dh@/ n. This refers to the problem
   of transferring data between machines with differing byte-order.
   The string "UNIX" might look like "NUXI" on a machine with a
   different "byte sex" (i.e. when transferring data from a
   little-endian to a big endian or vice-versa). See also,
   <big-endian>, <little-endian>, <swab>, and <bytesexual>.

<nybble> /nib'l/ [from v. `nibble' by analogy with `bite' -> `byte']
   n.  Four bits; one hexadecimal digit; a half-byte.  Though `byte'
   is now accepted technical jargon found in dictionaries, this useful
   relative is still slang.  Compare <crumb>, <taste>, <dynner>, see
   also <bit>.  Note: a correspondent in England alleges that this
   spelling is never used on his side of the pond, as British
   orthography would suggest the pronunciation /niebl/.

                                {= O =}

<Ob> /ob/ pref. Obligatory.  A piece of <netiquette> that acknowledges
   the author has been straying from the newsgroup's charter.  For
   example, if a posting in has nothing particularly to do
   with sex, the author may append "ObSex" (or "Obsex") and toss
   off a question or vignette about some unusual erotic act.

<obscure> adj. Used in an exaggeration of its normal meaning, to imply
   a total lack of comprehensibility.  "The reason for that last
   crash is obscure."  "The `find(1)' command's syntax is obscure."
   The phrase <moderately obscure> implies that it could be figured
   out but probably isn't worth the trouble.  <Obscure in the extreme>
   is a preferred emphatic form.

<OBFUSCATED C CONTEST> n. Annual contest run since 1984 over <the
   network> by Landon Curt Noll & friends.  The overall winner is he
   who produces the most unreadable, creative and bizarre working C
   program; various other prizes are awarded at the judges' whim.
   Given C's terse syntax and macro-preprocessor facilities, this
   gives contestants a lot of maneuvering room.  The winning programs
   often manage to be simultaneously a) funny, b) breathtaking works
   of art, and c) Horrible Examples of how *not* to code in C.

   This relatively short and sweet entry might help convey the flavor
   of obfuscated C:

     main(v,c)char**c;{for(v[c++]="Hello, world!\n)";(!!c)[*c]&&

   See also <hello, world!>.

<octal forty> /ok'tl for'tee/ n. Hackish way of saying "I'm drawing a
   blank" (octal 40 is the ASCII space character). See <wall>.

<off-by-one error> n. Exceedingly common error induced in many ways,
   such as by starting at 0 when you should have started at 1 or vice
   versa, or by writing < N instead of <= N or vice-versa.  Also
   applied to giving an object to the person next to the one who
   should have gotten it.  Often confused with <fencepost error>,
   which is properly a particular subtype of it.

<off the trolley> adj.  Describes the behavior of a program which
   malfunctions but doesn't actually <crash> or get halted by the
   operating system.  See <glitch>, <bug>, <deep space>.

<offline> adv.  Not now or not here.  Example: "Let's take this
   discussion offline."  Specifically used on <USENET> to suggest
   that a discussion be taken off a public newsgroup to email.

<old fart> n. Tribal elder.  A title self-assumed with remarkable
   frequency by (esp.) USENETters who have been programming for more
   than about twenty five years; frequently appears in SIGs attached
   to jargon file contributions of great archeological significance.
   This is a term of insult in second or third person but pride in
   first person.

<Old Testament> n. [C programmers] The first edition of the book
   describing <Classic C>; see <K&R>.

<ONE BELL SYSTEM (IT WORKS)> This was the output from the old Unix V6
   "1" command.  The "1" command also contained a random number
   generator which gave it a one in ten chance of recursively
   executing itself.

<one-liner wars> n. Popular game among hackers who code in the
   language APL (see <write-only language>). The objective is to see
   who can code the most interesting and/or useful routine in one line
   of operators chosen from APL's exceedingly <hairy> primitive set.
   [This is not *quite* as silly as it sounds; I myself have
   coded one-line <life> programs and once uttered a one-liner that
   performed lexical analysis of its input string followed by a
   dictionary lookup for good measure --- ESR] It has been reported
   that a similar amusement was practised among <TECO> hackers.

<ooblick> /oo'blik/ [from Dr. Seuss' "Bartholomew and the Ooblick"]
   n.  A bizarre semi-liquid sludge made from cornstarch and water.
   Enjoyed among hackers who make batches for playtime at parties for
   its amusing and extremely non-Newtonian behavior; it pours and
   splatters, but resists rapid motion like a solid and will even
   crack when hit by a hammer.  Often found near lasers.

<open> n. Abbreviation for "open (or left) parenthesis", used when
   necessary to eliminate oral ambiguity.  To read aloud the LISP form
   (DEFUN FOO (X) (PLUS X 1)) one might say: "Open def-fun foo, open
   eks close, open, plus ekx one, close close."  See <close>.

<open switch> [IBM, prob. fr. railroading] n. An unresolved issue.

<operating system> n. (Often abbreviated "OS") The foundation
   software of a machine, of course; that which schedules tasks,
   allocates storage, and presents a default interface to the user
   between applications.  The facilities the operating system provides
   and its general design philosophy exert an extremely strong
   influence on programming style and the technical culture that grows
   up around a machine.  Hacker folklore has been shaped primarily by
   the UNIX, ITS, TOPS-10, TOPS-20/TWENEX, VMS, CP/M, MS-DOS, and
   MULTICS operating systems (most importantly by ITS and UNIX). Each
   of these has its own entry, which see.

<Orange Book> n. The U.S. Government's standards document (Trusted
   Computer System Evaluation Criteria, DOD standard 5200.28-STD,
   December, 1985) characterizing secure computing architectures,
   defining levels A1 (most secure) through D (least).  Stock UNIXes
   are roughly C2.  See also <Red Book>, <Blue Book>, <Green Book>,
   <Silver Book>, <Purple Book>, <White Book>, <Pink-Shirt Book>,
   <Dragon Book>, <Aluminum Book>.

<ORIENTAL FOOD> n. Hackers display an intense tropism towards Oriental
   cuisine, especially Chinese, and especially of the spicier
   varieties such as Szechuan and Hunan.  This phenomenon (which has
   also been observed in subcultures which overlap heavily with
   hackerdom, most notably science-fiction fandom) has never been
   satisfactorily explained, but is sufficiently intense that one can
   assume the target of a hackish dinner expedition to be the best
   local Chinese place and be right at least 3 times out of 4. See
   also <ravs>, <great-wall>, <stir-fried random>.  Thai, Indian,
   Korean and Vietnamese cuisines are also quite popular.

<orphan> [UNIX] n. A process whose parent has died; one inherited by
   `init(1)'. Compare <zombie>.

<orthogonal> [from mathematics] adj. Mutually independent;
   well-separated; sometimes, irrelevant to.  Used in a generalization
   of its mathematical meaning to describe sets of primitives or
   capabilities which, like a vector basis in geometry, span the
   entire `capability space' of the system and are in some sense
   non-overlapping or mutually independent.  For example, in
   architectures such as the MC68000 where all or nearly all registers
   can be used interchangeably in any role with respect to any
   instruction, the register set is said to be orthogonal.  Or, in
   logic, the set of operators `not' and `or' is orthogonal, but the
   set `nand', `or' and `not' is not (because any one of these can be
   expressed in terms of the other two via De Morgan's Laws). Also
   used in comment on human discourse; "This may be orthogonal to the
   discussion, but...".

<OS> /oh ess/ 1. [Operating System] n. Acronym heavily used in email,
   occasionally in speech. 2. obs. n. On ITS, an output spy.  See
   Appendix A.

<OS/2> (oh ess too) n. The anointed successor to MS-DOS for Intel-286
   and (allegedly) 386-based micros; proof that IBM/Microsoft couldn't
   get it right the second time, either.  Cited here because
   mentioning it is usually good for a cheap laugh among hackers ---
   the design was so <baroque> and the implementation of 1.x so bad
   that three years after introduction you could still count the major
   APPs shipping for it on the fingers of two hands.  Often called
   "Half-an-OS".  A minority of DOS hackers retains hopes that the
   32-bit 2.x version will turn out a winner.  See <vaporware>,
   <monstrosity>, <cretinous>, <second-system effect>.

<overrun screw> [C programming] n. A variety of <fandango on core>
   produced by scribbling past the end of an array (C has no checks
   for this).  This is relatively benign and easy to spot if the array
   is static; if it is auto, the result may be to <smash the stack>.
   The term <overrun screw> is used esp. of scribbles beyond the end
   of arrays allocated with `malloc(3)'; this typically trashes the
   allocation header for the next block in the <arena>, producing
   massive lossage within malloc and (frequently) a core dump on the
   next operation to use `stdio(3)' or `malloc(3)' itself.  See <spam>; see
   also <memory leak>, <aliasing bug>, <precedence lossage>, <fandango
   on core>.

                                {= P =}

<page in> [MIT] v. To become aware of one's surroundings again after
   having paged out (see PAGE OUT).  Usually confined to the sarcastic
   comment, "So-and-so pages in.  Film at 11."  See <film at 11>.

<page out> [MIT] v. To become unaware of one's surroundings
   temporarily, due to daydreaming or preoccupation.  "Can you repeat
   that?  I paged out for a minute."  See <page in>.  Compare
   <glitch>, <thinko>.

<panic> [UNIX] v. An action taken by a process or the entire operating
   system when an unrecoverable error is discovered.  The action
   usually consists of: (1) displaying localized information on the
   controlling terminal, (2) saving, or preparing for saving, a memory
   image of the process or operating system, and (3) terminating the
   process or rebooting the system.

<param> /p@-ram'/ n. Speech-only shorthand for "parameter". Compare
   <arg>, <var>. The plural `params' is often further compressed to

<parity errors> pl.n. Those little lapses of attention or (in more
   severe cases) consciousness, usually brought on by having spent all
   night and most of the next day hacking.  "I need to go home and
   crash; I'm starting to get a lot of parity errors."  Derives from a
   relatively common but nearly always correctable transient error in
   RAM hardware.

<parse> [from linguistic terminology via AI research] v. 1. To
   determine the syntactic structure of a sentence or other utterance
   (close to the standard English meaning).  Example: "That was the
   one I saw you."  "I can't parse that."  2. More generally, to
   understand or comprehend.  "It's very simple; you just kretch the
   glims and then aos the zotz."  "I can't parse that."  3. Of
   fish, to have to remove the bones yourself (usually at a Chinese
   restaurant).  "I object to parsing fish" means "I don't want to
   get a whole fish, but a sliced one is okay."  A "parsed fish"
   has been deboned.  There is some controversy over whether
   "unparsed" should mean "bony", or also mean "deboned".

<patch> 1. n. A temporary addition to a piece of code, usually as a
   quick-and-dirty remedy to an existing bug or misfeature.  A patch
   may or may not work, and may or may not eventually be incorporated
   permanently into the program.  2. v. To insert a patch into a piece
   of code. 3. [in the UNIX world] n. a set of differences between two
   versions of source code, generated with `diff(1)' and intended to be
   mechanically applied using patch(1); often used as a way of
   distributing source code upgrades and fixes over <USENET>.

<pathological> [scientific computation] adj. Purposefully engineered
   as a worst case.  An algorithm which can be broken by pathological
   inputs may still be useful if such inputs are very unlikely to
   occur in practice.  The implication is that someone had to
   explicitly set out to break an algorithm in order to come up with
   such a crazy example.

<PBD> [abbrev of `Programmer Brain Damage'] n. Applied to bug reports
   revealing places where the program was obviously broken due to an
   incompetent or short-cited programmer.  Compare UBD; see also

<PC-ism> n. A piece of code or coding technique that takes advantage
   of the unprotected single-tasking environment in IBM PCs and the
   like.  e.g. by busy-waiting on a hardware register, direct diddling
   of screen memory, or using hard timing loops.  Compare
   <ill-behaved>, <vaxism>, <unixism>.  Also, <pc-ware> n., a program
   full of PC-ISMs on a machine with a more capable operating system.

<PD> /pee-dee/ adj. Common abbreviation for "public domain", applied
   to software distributed over <USENET> and from Internet archive
   sites.  Much of this software is not in fact "public domain" in
   the legal sense but travels under various copyrights granting
   reproduction and use rights to anyone who can <snarf> a copy.  See

<pdl> /pid'l/ or /pud'l/ [acronym for Push Down List] In ITS days, the
   preferred MITism for <stack>.  2.  Dave Lebling, one of the
   coauthors of <Zork>; (his <network address> on the ITS machines was
   at one time pdl@dms).  3. Program Design Language.  Any of a large
   class of formal and profoundly useless pseudo-languages in which
   <management> forces one to design programs.  <Management> often
   expects it to be maintained in parallel with the code.  Used
   jokingly as in, "Have you finished the PDL?"

<PDP-10> [Programmable Data Processor model 10] n. The machine that
   made timesharing real.  Looms large in hacker folklore due to early
   adoption in the mid-70s by many university computing facilities and
   research labs including the MIT AI lab, Stanford and CMU. Some
   aspects of the instruction set (most notably the bit-field
   instructions) are still considered unsurpassed.  Later editions
   were labelled `DECsystem-10' as a way of differentiating them from
   the PDP-11.  The '10 was eventually eclipsed by the PDP-11 and VAX
   machines and dropped from DEC's line in the early '80s, and in 1990
   to have cut one's teeth on one is considered something of a badge
   of honorable old-timerhood among hackers.  See <TOPS-10>, <ITS>,
   Appendix A.

<peek/poke> n.,v. The commands in most microcomputer BASICs for
   directly accessing memory contents at an absolute address; often
   extended to mean the corresponding constructs in any <HLL>. Much
   hacking on small, non-MMU micros consists of <peek>ing around
   memory, more or less at random, to find the location where the
   system keeps "interesting" stuff. Long and variably accurate, lists
   of such addresses for various computers circulate. The results of
   <poke>s at these addresses may be highly useful, mildly amusing,
   useless but neat or (most likely) total <lossage> (see <killer

<percent-s> /per-sent' ess/ [From "%s", the formatting sequence in
   C's `printf(3)' library function used to indicate that an arbitrary
   string may be inserted] n. An unspecified person or object.  "I
   was just talking to some percent-s in administration."  Compare

<perf> /perf/ n. See <chad> (sense #1).  The term "perfory" is also

<PERL> [Practical Extraction and Report Language, aka Pathologically
   Eclectic Rubbish Lister] n. An interpreted language developed by
   Larry Wall (, author of `patch(1)') and
   distributed over USENET.  Superficially resembles `awk(1)', but is
   much more arcane (see AWK).  Increasingly considered a <language of
   choice> by UNIX sysadmins, who are almost always incorrigible
   hackers.  Perl has been described, in a parody of a famous remark
   about `lex(1)', as the "Swiss-army chainsaw" of UNIX programming.

<pessimal> /pes'i-ml/ [Latin-based antonym for "optimal"] adj.
   Maximally bad.  "This is a pessimal situation."  Also <pessimize>
   v.  to make as bad as possible.  These words are the obvious
   Latin-based antonyms for "optimal" and "optimize", but for some
   reason they do not appear in most English dictionaries, although
   "pessimize" is listed in the Oxford English Dictionary.

<pessimizing compiler> /pes'i-miez-ing kuhm-pie'lr/ [antonym of
   `optimizing compiler'] n. A compiler that produces object code that
   is worse than the straightforward or obvious translation.  The
   implication is that the compiler is actually trying to optimize the
   program, but through stupidity is doing the opposite.  A few
   pessimizing compilers have been written on purpose, however, as

<phase> 1. n. The phase of one's waking-sleeping schedule with respect
   to the standard 24-hour cycle.  This is a useful concept among
   people who often work at night according to no fixed schedule.  It
   is not uncommon to change one's phase by as much as six hours/day
   on a regular basis.  "What's your phase?"  "I've been getting in
   about 8 PM lately, but I'm going to <wrap around> to the day
   schedule by Friday."  A person who is roughly 12 hours out of
   phase is sometimes said to be in "night mode".  (The term "day
   mode" is also , but less frequently, used, meaning you're working
   9 to 5 (or more likely 10 to 6)).  The act of altering one's cycle
   is called "changing phase"; "phase shifting" has also been
   recently reported from Caltech.  2. <change phase the hard way>: to
   stay awake for a very long time in order to get into a different
   phase.  3. <change phase the easy way>: To stay asleep etc.
   However, some claim that either staying awake longer or sleeping
   longer is easy, an that it's *shortening* your day or night
   that's hard.  The phenomenon of "jet lag" that afflicts travelers
   who cross many time-zone boundaries may be attributed to two
   distinct causes: the strain of travel per se, and the strain of
   changing phase.  Hackers who suddenly find that they must change
   phase drastically in a short period of time, particularly the hard
   way, experience something very like jet lag without travelling.

<phase of the moon> n. Used humorously as a random parameter on which
   something is said to depend.  Sometimes implies unreliability of
   whatever is dependent, or that reliability seems to be dependent on
   conditions nobody has been able to determine.  "This feature
   depends on having the channel open in mumble mode, having the foo
   switch set, and on the phase of the moon."

   True story: Once upon a time, a program written by Gerry Sussman
   (professor of Electrical Engineering at MIT) and Guy Steele had a
   bug that really did depend on the phase of the moon!  There is a
   little subroutine that had traditionally been used in various
   programs at MIT to calculate an approximation to the moon's true
   phase; the phase is then printed out at the top of program
   listings, for example, along with the date and time, purely for
   fun.  (Actually, since hackers spend a lot of time indoors, this
   might be the only way they would ever know what the moon's phase
   was!)  Steele incorporated this routine into a LISP program that,
   when it wrote out a file, would print a `timestamp" line almost 80
   characters long.  Very occasionally the first line of the message
   would be too long and would overflow onto the next line, and when
   the file was later read back in the program would <barf>.  The
   length of the first line depended on the precise time when the
   timestamp was printed, and so the bug literally depended on the
   phase of the moon!

   The first paper edition of the Jargon File (Steele-1983) included
   an example of this bug, but the typesetter "corrected" it.  This
   has since been described as the phase-of-the-moon-bug bug.

<pig, run like a> adj. To run very slowly on given hardware, said of
   software.  Distinct from <hog>.

<ping> /ping/ [from TCP/IP terminology] n.,v. 1. Slang term for a
   small network message (ICMP ECHO) sent by a computer to check for
   the presence and aliveness of another.  Occasionally used as a
   phone greeting.  See <ACK>, also <ENQ>. 2.  To verify the presence
   of.  3. To get the attention of.  From the Unix command by the same
   name (an acronym of "Packet INternet Groper) that sends an ICMP
   ECHO packet to another host.  This was probably contrived to match
   submariners' "ping" (sonar ranging pulse).

<Pink-Shirt Book> `The Peter Norton Programmer's Guide to the IBM
   PC'.  The original cover featured a picture of Peter Norton with a
   silly smirk on his face, wearing a pink shirt.  Perhaps in
   recognition of this usage, the current edition has a different
   picture of Norton wearing a pink shirt.

<PIP> /pip/ v. obs. To copy, from the program PIP on CP/M and RSX-11
   that was used for file copying (and in RSX for just about every
   other file operation you might want to do). Obsolete, but still
   occasionally heard.

<pipeline> [UNIX, orig. by Doug McIlroy; now also used under MS-DOS
   and elsewhere] n. A chain of <filter> programs connected
   "head-to-tail", so that the output of one becomes the input of
   the next.  Under UNIX, user utilities can often be implemented or
   at least prototyped by a suitable collection of pipelines and
   temp-file grinding encapsulated in a shell script; this is much
   less effort than writing C every time, and the capability is
   considered one of UNIX's major winning features.

<pizza, ANSI standard> /pee'tz@, an'see stan'd@rd/ [CMU] Pepperoni
   and mushroom pizza.  Coined allegedly because most pizzas ordered
   by CMU hackers during some period leading up to mid-1990 were of
   that flavor.  See also <rotary debugger>.

<plain-ASCII> Syn. <flat-ASCII>.

<playpen> [IBM] n. A room where programmers work.  Compare <salt

<playte> /din'r/ 16 bits, by analogy with <nybble> and byte.  Usage:
   rare and extremely silly.  See also <dynner>.

<plingnet> /pling'net/ n. Syn. <UUCPNET>. Also see <COMMONWEALTH

<plonk> [USENET] The sound a <newbie> makes as he falls to the bottom
   of a <kill file>.  Almost exclusively used in the <newsgroup>
   "talk.bizarre", this term (usually written "*plonk*") is a
   form of public ridicule.

<plugh> /ploogh/ [from the <ADVENT> game] v. See <xyzzy>.

<PM> /pee em/ 1. [from "preventive maintenance"] v. to bring down a
   machine for inspection or test purposes; see <scratch monkey>. 2.
   n.  Abbrev. for "Presentation Manager", an <elephantine> OS/2
   graphical user interface.

<P.O.D.> /pee-oh-dee/ Acronym for `Piece Of Data' (as opposed to a
   code section). Usage: pedantic and rare.

<pod> n. A Diablo 630 (or, latterly, any impact letter quality
   printer).  From the DEC-10 PODTYPE program used to feed formatted
   text to same.

<poll> v.,n. 1. The action of checking the status of an input line,
   sensor, or memory location to see if a particular external event
   has been registered. 2. To ask.  "I'll poll everyone and see where
   they want to go for lunch."

<polygon pusher> n. A chip designer who spends most of his/her time at
   the physical layout level (which requires drawing *lots* of
   multi-colored polygons). Also "rectangle slinger".

<POM> /pee-oh-em/ n. <Phase of the moon>.  Usage: usually used in the
   phrase "POM dependent" which means <flaky>.

<POP> also <POPJ> /pop-jay/ [based on the stack operation that removes
   the top of a stack, and the fact that procedure return addresses
   are saved on the stack] 1. v.  To remove something from a <stack>
   or <pdl>.  If a person says he has popped something from his stack,
   he means he has finally finished working on it and can now remove
   it from the list of things hanging over his head.  2. To return
   from a digression (the J-form derives specifically from a <PDP-10>
   assembler instruction).  By verb doubling, "Popj, popj" means
   roughly, "Now let's see, where were we?"  See <RTI>.

<PPN> /pip'n/ [from "Project-Programmer Number"] n. A user-ID under
   <TOPS-10> and its various mutant progeny at SAIL and BBN and
   CompuServe and elsewhere.  Old-time hackers from the PDP-10 era
   sometimes use this to refer to user IDs on other systems as well.

<precedence lossage> /pre's@-dens los'j/ [C programmers] n. Coding
   error in an expression due to unexpected grouping of arithmetic or
   logical operators by the compiler.  Used esp. of certain common
   coding errors in C due to the nonintuitively low precedence levels
   of &, | and ^. Can always be avoided by suitable use of
   parentheses.  See <aliasing bug>, <memory leak>, <smash the stack>,
   <fandango on core>, <overrun screw>.

<prepend> /pree`pend'/ [by analogy with "append"] v. To prefix.
   Like "append", but unlike "prefix" or "suffix" as a verb, the
   direct object is always the thing being added and not the original
   word (character string, etc).  No, this is *not* standard
   English, yet!

<pretty pictures> n. [scientific computation] The next step up from
   <numbers>.  Interesting graphical output from a program which may
   not have any real relationship to the reality the program is
   intended to model.  Good for showing to <management>.

<prettyprint> v. 1. To generate `pretty' human-readable output from a
   hairy internal representation; esp. used for the process of
   <grind>ing (sense #2) LISP code. 2. To format in some particularly
   slick and nontrivial way.  See <grind>.

<prime time> [from TV programming] n. Normal high-usage hours on a
   timesharing system, the `day shift'. Avoidance of prime time is a
   major reason for <night mode> hacking.

<priority interrupt> [from the hardware term] n. Describes any
   stimulus compelling enough to yank one right out of <hack mode>.
   Classically used to describe being dragged away by an <SO> for
   immediate sex, but may also refer to more mundane interruptions
   such as a fire alarm going off in the near vicinity.  Also called
   an NMI (non maskable interrupt) especially in PC-land.

<Programmer's Cheer> "Shift to the left!  Shift to the right!  Push
   down, pop up!  Byte!  Byte!  Byte!"  A joke so old it has hair on

<propeller head> n. Used by hackers, this is syn. with <computer
   geek>.  Non-hackers sometimes use it to describe all techies.
   Prob.  derives from SF fandom's tradition of propeller beanies as
   fannish insignia (though nobody actually wears them except as a

<protocol> n. See <do protocol>.

<prowler> [UNIX] n. A <DEMON> that is run periodically (typically once
   a week) to seek out and erase core files, truncate administrative
   logfiles, nuke lost+found directories, and otherwise clean up the
   cruft that tends to pile up in the corners of a file system.  See
   also <GFR>, <reaper>, <skulker>.

<pseudo> /soo'do/ [USENET] n. 1. An electronic-mail or <USENET>
   persona adopted by a human for amusement value or as a means of
   avoiding negative repercussions of his/her net.behavior; a `nom de
   USENET', often associated with forged postings designed to conceal
   message origins.  Perhaps the best-known and funniest hoax of this
   type is <biff>. 2. Notionally, a <flamage>-generating AI program
   simulating a USENET user.  Many flamers have been accused of
   actually being such entities, despite the fact that no AI program
   of the required sophistication exists.  However, in 1989 there was
   a famous series of forged postings that used a
   phrase-frequency-based travesty generator to simulate the styles of
   several well-known flamers based on large samples of their back
   postings.  A significant number of people were fooled by these, and
   the debate over their authenticity was only settled when the
   perpetrator of the hoax came publicly forward to admit the deed.

<pseudoprime> n. A backgammon prime (six consecutive occupied points)
   with one point missing.  This term is an esoteric pun derived from
   a mathematical method which, rather than determining precisely
   whether a number is prime (has no divisors), uses a statistical
   technique to decide whether the number is "probably" prime.  A
   number that passes this test is called a pseudoprime.  The hacker
   backgammon usage stems from the idea that pseudoprime is almost as
   good as a prime: it does the job of a prime until proven otherwise,
   and that probably won't happen.

<pseudosuit> n. A <suit> wannabee; a hacker who's decided that he
   wants to be in management or administration and begins wearing
   ties, sport coats and (shudder!) suits voluntarily.  Chacun a son

<punt> [from the punch line of an old joke referring to American
   football: "Drop back 15 yards and punt"] v. To give up, typically
   without any intention of retrying.  "Let's punt the movie
   tonight."  "I was going to hack all night to get this feature in,
   but I decided to punt" may mean that you've decided not to stay up
   all night, and may also mean you're not ever even going to put in
   the feature.

<Purple Book> n. The `System V Interface Definition'.  The covers
   of the first editions were an amazingly nauseating shade of
   off-lavender.  See also <Red Book>, <Blue Book>, <Green Book>,
   <Silver Book>, <Orange Book>, <White Book>, <Pink-Shirt Book>,
   <Dragon Book>, <Aluminum Book>.

<PUSH> [based on the stack operation that puts the current information
   on a stack, and the fact that procedure call addresses are saved on
   the stack] Also PUSHJ (push-jay), based on the PDP-10 procedure
   call instruction.  1. To put something onto a <stack> or <pdl>.  If
   a person says something has been pushed onto his stack, he means
   yet another thing has been added to the list of things hanging over
   his head for him to do.  2. v. To enter upon a digression, to save
   the current discussion for later.  Antonym of <POP>, <POPJ>; see
   also <stack>, <pdl>.

<psychedelicware> [Great Britain] n. Syn. <display hack>.

                                {= Q =}

<quadruple bucky> n., obs. On a <space-cadet keyboard>, use of all
   four of the shifting keys control, meta, hyper, and super while
   typing a character key.  This was very difficult to do!  One
   accepted technique was to press the left-control and left-meta keys
   with your left hand, the right-control and right-meta keys with
   your right hand, and the fifth key with your nose.  Thus, this
   combination was very seldom used in practice, because when you
   invent a new command you usually assign it to some character that
   is easier to type.  If you want to imply that a program has
   ridiculously many commands or features, you can say something like
   "Oh, the command that makes it spin all the tapes while whistling
   Beethoven's Fifth Symphony is quadruple-bucky-cokebottle". See
   <double bucky>, <bucky bits>.

<quantum bogodynamics> /kwahn'tm boh`goh-die-nam'iks/ n. Theory which
   characterizes the universe in terms of bogon sources (such as
   politicians, used-car salesmen, TV evangelists, and SUITs in
   general), bogon sinks (such as taxpayers and computers), and
   bogosity potential fields.  Bogon absorption, of course, causes
   human beings to behave mindlessly and machines to fail (and may
   cause them to emit secondary bogons as well); however, the precise
   mechanics of the bogon-computron interaction are not yet understood
   and remain to be elucidated.  Quantum bogodynamics is most
   frequently invoked to explain the sharp increase in hardware and
   software failures in the presence of suits; the latter emit bogons
   which the former absorb.  See <bogon>, <computron>, <suit>.

<ques> /kwess/ 1. n. The question mark character ("?").  2. interj.
   What?  Also frequently verb-doubled as "ques ques?"  See <wall>.

<qux> /kwuhks/ The fourth of the standard metasyntactic variables,
   after <baz> and before the QUU*X series.  See <foo>, <bar>, <baz>,
   <quux>.  Note that this appears to a be recent mutation from
   <quux>, and that many versions of the standard series just run
   <foo>, <bar>, <baz>, <quux>,...

<quux> /kwuhks/ [invented by Steele] Mythically, from the Latin
   semi-deponent verb quuxo, quuxare, quuxandum iri; noun form
   variously "quux" (plural "quuces", anglicized to "quuxes")
   and "quuxu" (genitive plural is "quuxuum", for four u-letters
   out of seven total).] 1.  Originally, a meta-word like <foo> and
   <foobar>.  Invented by Guy Steele for precisely this purpose when
   he was young and naive and not yet interacting with the real
   computing community.  Many people invent such words; this one seems
   simply to have been lucky enough to have spread a little.  In an
   eloquent display of poetic justice, it has returned to the
   originator in the form of a nickname, as punishment for inventing
   this bletcherous word in the first place.  2. interj. See <foo>;
   however, denotes very little disgust, and is uttered mostly for the
   sake of the sound of it.  3. Guy L. Steele in his persona as "The
   Great Quux", which is somewhat infamous for light verse and for
   the "Crunchly" cartoons.  4. quuxy: adj.  Of or pertaining to a

<QWERTY> /kwer'tee/ adj. Pertaining to a standard English typewriter
   keyboard, as opposed to Dvorak or foreign-language layouts or a
   <space-cadet keyboard> or APL keyboard.

                                {= R =}

<random> adj. 1. Unpredictable (closest to mathematical definition);
   weird.  "The system's been behaving pretty randomly."  2.
   Assorted; undistinguished.  "Who was at the conference?"  "Just
   a bunch of random business types."  3.  Frivolous; unproductive;
   undirected (pejorative).  "He's just a random loser."  4.
   Incoherent or inelegant; not well organized.  "The program has a
   random set of misfeatures."  "That's a random name for that
   function."  "Well, all the names were chosen pretty randomly."
   5.  Gratuitously wrong, i.e., poorly done and for no good apparent
   reason.  For example, a program that handles file name defaulting
   in a particularly useless way, or an assembler routine that could
   easily have been coded using only three registers, but randomly
   uses seven for assorted non-overlapping purposes, so that no one
   else can invoke it without first saving four extra registers.  6.
   In no particular order, though deterministic.  "The I/O channels
   are in a pool, and when a file is opened one is chosen randomly."
   n.  7. A random hacker; used particularly of high school students
   who soak up computer time and generally get in the way.  8.
   (occasional MIT usage) One who lives at Random Hall.  See also <J.
   Random>, <some random X>.

<random numbers> n. When one wishes to specify a large but random
   number of things, and the context is inappropriate for <N>, certain
   numbers are preferred by hacker tradition (that is, easily
   recognized as placeholders). These include

     17 Long described at MIT as "the least random number", see 23.
     23 Sacred number of Eris, Goddess of Discord (along with 17 & 5).
     42 The Answer to the Question of Life, the Universe and Everything.
     69 From the sexual act. This one was favored in MIT's ITS culture.
     105 69 hex = 105 dec, and 69 dec = 105 oct
     666 The Number of the Beast.

   For further enlightenment, consult the `Principia Discordia',
   `The Hitchhiker's Guide To The Galaxy', any porn movie, and the
   Christian Bible's `Book Of Revelations'. See also

<randomness> n. An unexplainable misfeature; gratuitous inelegance.
   Also, a <hack> or <crock> which depends on a complex combination of
   coincidences (or rather, the combination upon which the crock
   depends for its accidental failure to malfunction).  "This hack
   can output characters 40-57 by putting the character in the
   accumulator field of an XCT and then extracting 6 bits --- the low
   two bits of the XCT opcode are the right thing."  "What

<rape> v. To (metaphorically) screw someone or something, violently;
   in particular, to destroy a program or information irrecoverably
   Usage: often used in describing file-system damage.  "So-and-so
   was running a program that did absolute disk I/O and ended up
   raping the master directory."

<rare> [UNIX] adj. CBREAK mode (character-by-character with interrupts
   enabled).  Distinguished from `raw' and `cooked'; the phrase
   "half-cooked (rare?)" is used in the V7/BSD manuals to describe
   the mode.  Usage: rare.

<raster blaster> n. [Cambridge] Specialized hardware for <bitblt>
   operations.  Allegedly inspired by analogy with "Rasta Blasta",
   British slang for the sort of portable stereo/radio/tapedeck
   Americans call a `boom box' or `ghetto blaster'.

<raster burn> n. Eyestrain brought on by too many hours of looking at
   low-res, poorly tuned or glare-ridden monitors, esp.  graphics
   monitors.  See <terminal illness>.

<rave> [WPI] v. 1. To persist in discussing a specific subject.  2. To
   speak authoritatively on a subject about which one knows very
   little.  3. To complain to a person who is not in a position to
   correct the difficulty.  4. To purposely annoy another person
   verbally.  5. To evangelize.  See <flame>.  Also used to describe a
   less negative form of blather, such as friendly bullshitting.
   <Rave> differs slightly from <flame> in that <rave> implies that it
   is the manner or persistence of speaking that is annoying, while
   <flame> implies somewhat more strongly that the subject matter is
   annoying as well.

<rave on!> imp. Sarcastic invitation to continue a <rave>, often by
   someone who wishes the raver would get a clue but realizes this is

<ravs> /ravz/, also CHINESE RAVS n.  Kuo-teh.  A Chinese appetizer,
   known variously in the plural as dumplings, potstickers and (around
   Boston) `Peking Ravioli'.  The term "rav" is short for
   "ravioli", which among hackers always means the Chinese kind
   rather than the Italian kind.  Both consist of a filling in a pasta
   shell, but the Chinese kind uses a thinner pasta and is cooked
   differently, either by steaming or frying.  A rav or dumpling can
   be steamed or fried, but a potsticker is always the fried kind (so
   called because it sticks to the frying pot and has to be scraped
   off).  "Let's get hot-and-sour soup and three orders of ravs."
   See also <ORIENTAL FOOD>.

<READ.ME file> n. By convention, the top-level directory of a UNIX
   source distribution always contains a file named `READ.ME' (or
   README, or (rarely) ReadMe) which is a hacker's-eye introduction
   containing a pointer to more detailed documentation, credits,
   miscellaneous revision history notes, etc.

<read-only user> n. Describes a <luser> who uses computers almost
   exclusively for reading USENET, bulletin boards and email, as
   opposed to writing code or purveying useful information.  See

<real programmer> [indirectly, from the book `Real Men Don't Eat
   Quiche'] n. A particular sub-variety of hacker, one possessed of a
   flippant attitude towards complexity that is arrogant even when
   justified by experience.  The archetypal `real programmer' likes to
   program on the <bare metal>, and is very good at same; he remembers
   the binary opcodes for every machine he's every programmed; thinks
   that HLLs are sissy; and he uses a debugger to edit his code
   because full-screen editors are for wimps.  Real Programmers aren't
   satisfied with code that hasn't been <bum>med into a state of
   <tense>ness just short of rupture.  Real Programmers never use
   comments or write documentation; "If it was hard to write", says
   the Real Programmer, "it should be hard to understand."  Real
   Programmers can make machines do things that were never in their
   spec sheets; in fact, they're seldom really happy unless doing so.
   A Real Programmer's code can awe you with its fiendish brilliance
   even as it appalls by its level of crockishness.  Real Programmers
   live on junk food and coffee, hang line-printer art on their walls,
   and terrify the crap out of other programmers --- because someday,
   somebody else might have to try to understand their code in order
   to change it.  Their successors generally consider it a <Good
   Thing> that there aren't many Real Programmers around any more.

<Real Soon Now> [orig. from SF's fanzine community, popularized by
   Jerry Pournelle's BYTE column] adj.  1. Supposed to be available
   (or fixed, or cheap, or whatever) real soon now according to
   somebody, but the speaker is quite skeptical.  2. When the
   gods/fates/other time commitments permit the speaker to get to it.
   Often abbreviated RSN.

<real time> adv. Doing something while people are watching or waiting.
   "I asked her how to find the calling procedure's program counter
   on the stack and she came up with an algorithm in real time."

<real user> n. 1. A commercial user.  One who is paying "real" money
   for his computer usage.  2. A non-hacker.  Someone using the system
   for an explicit purpose (research project, course, etc.).  See
   <user>.  Hackers who are also students may also be real users.  "I
   need this fixed so I can do a problem set.  I'm not complaining out
   of randomness, but as a real user."  See also <luser>.

<Real World> n. 1. In programming, those institutions at which
   programming may be used in the same sentence as FORTRAN, COBOL,
   RPG, <IBM>, etc.  Places where programs do such commercially
   necessary but intellectually uninspiring things as compute payroll
   checks and invoices.  2. To programmers, the location of
   non-programmers and activities not related to programming.  3. A
   universe in which the standard dress is shirt and tie and in which
   a person's working hours are defined as 9 to 5.  4. The location of
   the status quo.  5. Anywhere outside a university.  "Poor fellow,
   he's left MIT and gone into the real world."  Used pejoratively by
   those not in residence there.  In conversation, talking of someone
   who has entered the real world is not unlike talking about a
   deceased person.  See also <fear and loathing>, <mundane>, and

<reaper> n. A <prowler> which GFRs files (see <GFR>). A file removed
   in this way is said to have been "reaped".

<rectangle slinger> n. See <polygon pusher>.

<recursion> n. See <recursion>.  See also <tail recursion>.

<RECURSIVE ACRONYMS> pl.n. A hackish (and especially MIT) tradition is
   to choose acronyms which refer humorously to themselves or to other
   acronyms.  The classic examples were two MIT editors called EINE
   ("EINE Is Not EMACS") and ZWEI ("ZWEI Was EINE Initially").
   More recently, <GNU> (q.v., sense #1) is said to stand for "GNU's
   Not UNIX!"

<Red Book> n. 1. Informal name for one of the three standard
   references on PostScript (`PostScript Language Reference Manual',
   Adobe Systems, Addison-Wesley 1985 QA76.73.P67P67, ISBN
   0-201-10174-2); the others are known as the <Green Book> and <Blue
   Book>.  2. `Smalltalk-80: The Interactive Programming
   Environment', Adele Goldberg, Addison-Wesley 1984,
   QA76.8.S635G638, ISBN 0-201-11372-4 (this is also associated with
   blue and green books).  3. Any of the 1984 standards issued by the
   CCIT 8th plenary assembly.  Until now, these have changed color
   each review cycle (1988 was <Blue Book>, 1992 will be <Green
   Book>); however, it is rumored that this convention is going to be
   dropped befor 1992.  These include, among other things, the X.400
   email spec and the Group 1 through 4 fax standards.  4. The new
   version of the <Green Book> (sense #4), "IEEE 1003.1-1990", aka
   "ISO 9945-1", is (because of the colour and the fact that it is
   printed on A4 paper), known in the USA as "The Ugly Red Book That
   Won't Fit On The Shelf", and in Europe as "The Ugly Red Book
   That's A Sensible Size".  See also <Green Book>, <Blue Book>,
   <Purple Book>, <Silver Book>, <Orange Book>, <White Book>,
   <Pink-Shirt Book>, <Dragon Book>, <Aluminum Book>.

<regexp> /reg'exp/ [UNIX] n. 1. Common written and spoken abbreviation
   for `regular expression', one of the wildcard patterns used, e.g.,
   by UNIX utilities such as `grep(1)', `sed(1)' and `awk(1)'. These use
   conventions similar to but more elaborate than those described
   under <glob>.  2. Name of a well-known PD regexp-handling package
   in portable C, written by revered USENETter Henry Spencer

<reincarnation, cycle of> n. Term used to refer to a well-known effect
   whereby function in a computing system family is migrated out to
   special purpose peripheral hardware for speed, then the peripheral
   evolves towards more computing power as it does its job, then
   somebody notices that it's inefficient to support two asymmetrical
   processors in the architecture and folds the function back into the
   main CPU, at which point the cycle begins again.  Several
   iterations of this cycle have been observed in graphics processor
   design, and at least one or two in communications and
   floating-point processors.  Also known as "the Wheel of Life",
   "the Wheel of Samsara", and other variations of the basic
   Hindu/Buddhist theological idea.

<religious issues> n. Questions which seemingly cannot be raised
   without touching off holy wars>, such as "What is the best
   editor/language/operating system/architecture/shell/mail
   reader/news reader". See also <theology>.

<replicator> n. Any construct that acts to produce copies of itself;
   this could be a living organism, an idea (see <meme>), a program
   (see <worm>, <wabbit> and <virus>), a pattern in a cellular
   automaton (see <life>, sense #1), or (speculatively) a robot.

<retcon> /ret'-con/ ["retroactive continuity", from USENET's
   rec.arts.comics] 1. n. the common situation in pulp fiction (esp.
   comics, soaps) where a new story "reveals" new things about
   events previous stories, usually leaving the "facts" the same
   (thus preserving "continuity") while completely changing their
   interpretation.  E.g., revealing that a whole season's episodes of
   Dallas was a dream was a retcon.  2.  v.t. To write such a story
   about (a character or fictitious object).  Thus, "Byrne has
   retconned Superman's cape so that it is no longer unbreakable".
   3. v.i. Used of something "transformed" in this way -
   "Marvelman's old adventures were retconned into synthetic
   dreams", "Swamp Thing was retconned from a transformed person
   into a sentient vegetable."

   [This is included because it's a good example of hackish linguistic
   innovation in a field completely unrelated to computers.  The word
   "retcon" will probably spread through comics fandom and lose its
   association with hackerdom within a couple of years; for the
   record, it started here. -- ESR]

<retrocomputing> /ret'-roh-k@m-pyoo'ting/ n. Refers to emulations of
   way-behind-the state-of-the-art hardware or software, or
   implementations of never-was-state-of-the-art; esp. if such
   implementations are elaborate practical jokes and/or parodies of
   more `serious' designs.  Perhaps the most widely distributed
   retrocomputing utility was the `pnch(6)' program on V7 and other
   early UNIX versions, which would accept up to 80 characters of text
   argument and display the corresponding pattern in Hollerith card
   code.  Other well-known retrocomputing hacks have included the
   programming language <INTERCAL>, a jcl-emulating shell for UNIX,
   the card-punch-emulating editor named 029, and various elaborate
   PDP-11 hardware emulators and RT-11 OS emulators written just to
   keep an old, sourceless <Zork> binary running.

<RFC> /ahr ef see/ n. Request For Comment.  One of a long-established
   series of numbered Internet standards widely followed by commercial
   and PD software in the Internet and UNIX communities.  Perhaps the
   single most influential one has been RFC-822 (the Internet
   mail-format standard). The RFCs are unusual in that they are
   floated by technical experts acting on their own initiative and
   reviewed by the Internet at large, rather than formally promulgated
   through an institution such as ANSI.  For this reason they remain
   known as RFCs even once adopted.

<RFE> n. 1. Request For Enhancement.  2. [Bellcore, Sun] Radio Free
   Ethernet, a system (originated by Peter Langston) for broadcasting
   audio among Sun SPARCstations over the ethernet.

<rice box> [from ham radio slang] n. Any Asian-made commodity
   computer, esp. an 8086, 80286, 80386 or 80486-based machine built
   to IBM PC-compatible ISA or EISA-bus standards.

<Right Thing, The> n. That which is *obviously* the correct or
   appropriate thing to use, do, say, etc.  Often capitalized, always
   emphasized in speech as though capitalized.  Use of this term often
   implies that in fact reasonable people may disagree.  "Never let
   your conscience keep you from doing the right thing!"  "What's
   the right thing for LISP to do when it reads (a mod 0)? Should it
   return a, or give a divide-by-zero error?"  Antonym: <Wrong

<RL> [MUD community] n. Real Life. "Firiss laughs in RL" means
   Firiss's player is laughing.

<roach> [Bell Labs] v. To destroy, esp. of a data structure.  Hardware
   gets <toast>ed, software gets roached.

<robust> adj. Said of a system which has demonstrated an ability to
   recover gracefully from the whole range of exception conditions in
   a given environment.  One step below <bulletproof>.  Compare
   <smart>, oppose <brittle>.

<root> n. [UNIX] 1. The top node of the system directory structure
   (home directory of the root user).  2. The "superuser" account
   that ignores permission bits, user number zero on a UNIX system.
   This account has the user name `root'.  3. By extension, the
   privileged system-maintenance login on any OS.  4. Thus, <root
   mode>: Syn.  with <wizard mode> or <wheel mode>.  Like these, it is
   often generalized to describe privileged states in systems other
   than OSs.  5. <go root>: to temporarily enter <root mode> in order
   to perform a privileged operation.  This use is deprecated in
   Australia, where v. "root" is slang for "to have sex with".

<rotary debugger> [Commodore] n.  Essential equipment for those late
   night or early morning debugging sessions.  Mainly used as
   sustenance for the hacker.  Comes in many decorator colors such as
   Sausage, Pepperoni, and Garbage.  See <pizza, ANSI standard>.

<rogue> [UNIX] n. Graphic Dungeons-And-Dragons-like game written under
   BSD UNIX and subsequently ported to other UNIX systems.  The
   original BSD `curses(3)' screen-handling package was hacked together
   by Ken Arnold to support `rogue(6)' and has since become one of
   UNIX's most important and heavily used application libraries.
   Nethack, Omega, Larn and an entire subgenre of computer dungeon
   games all took off from the inspiration provided by `rogue(6)'.  See

<room-temperature IQ> [IBM] 80 or below.  Used in describing the
   expected intelligence range of the <luser>.  As in "Well, but
   how's this interface gonna play with the room-temperature IQ
   crowd?"  See <drool-proof paper>.

<rot13> /rot-ther'teen/ [USENET, from "rotate alphabet 13 places"]
   n.,v. The simple encryption of replacing each English letter with
   the one 13 places forward or back along the alphabet, so that "The
   butler did it!" becomes "Gur ohgyre qvq vg!"  Most Usenet news
   reading and posting programs include a rot13 feature.  It is used
   as if to enclose the text in a sealed wrapper that the reader must
   choose to open, for posting things that might offend some readers,
   answers to puzzles, or discussion of movie plot surprises.

<RSN> adj. See <Real Soon Now>.

<RTFM> /ahr-tee-ef-em/ [UNIX] Abbrev. for "Read The Fucking Manual".
   1. Used by GURUs to brush off questions they consider trivial or
   annoying.  Compare <Don't do that, then!>.  2. Used when reporting
   a problem to indicate that you aren't just asking out of
   <randomness>.  "No, I can't figure out how to interface UNIX to my
   toaster and yes I have RTFM."  Unlike sense #1 this use is
   considered polite.

<RTI> /ahr-tee-ie/ interj. The mnemonic for the `return from
   interrupt' instruction on Intel microprocessors.  Equivalent to
   "Now, where was I?" or used to end a conversational digression.
   See <POP>, <POPJ>.

<rude> [WPI] adj. 1. (of a program) Badly written.  2.  Functionally
   poor, e.g. a program which is very difficult to use because of
   gratuitously poor (random?) design decisions.  See <cuspy>.

<runes> pl.n. 1. Anything that requires <heavy wizardry> or <black
   art> to <parse>; core dumps, JCL commands, or even code in a
   language you don't have the faintest idea how to read.  Compare
   <casting the runes>.  2. Special display characters (for example,
   the high-half graphics on an IBM PC).  3. <runic> adj. Syn.
   <obscure>.  VMS fans sometimes refer to UNIX as `Runix'; UNIX fans
   return the compliment by expanding VMS to `Vachement Mauvais
   Systeme' (lit. "Cowlike Bad System").

                                {= S =}

<sacred> adj. Reserved for the exclusive use of something (a
   metaphorical extension of the standard meaning).  "Accumulator 7
   is sacred to the UUO handler."  Often means that anyone may look
   at the sacred object, but clobbering it will screw whatever it is
   sacred to.  Example: The comment "Register 7 is sacred to the
   interrupt handler" appearing in a program would be interpreted by
   a hacker to mean that one part of the program, the "interrupt
   handler", uses register 7, and if any other part of the program
   changes the contents of register 7 dire consequences are likely to

<sadistics> /s@'dis'tiks/ n. University slang for statistics and
   probability theory, often used by hackers.

<saga> [WPI] n. A cuspy but bogus raving story dealing with N random
   broken people.

<sagan> [from Carl Sagan's TV series on PBS, think "Billions and
   Billions"] n. A large quantity of anything.  "There's a sagan
   different ways to tweak EMACS."  "The US Government spends sagans
   on military hardware."

<SAIL> n. Stanford University Artificial Intelligence Lab.  An
   important site in the early development of LISP; with the MIT AI
   LAB, CMU and the UNIX community, one of the major founts of hacker
   culture traditions.  The SAIL machines were shut down in late May
   1990, scant weeks after the MIT AI lab's ITS cluster went down for
   the last time.

<salescritter> /sayls'kri-tr/ n. Pejorative hackerism for a computer
   salesperson.  Hackers tell the following joke:

     Q. What's the difference between a used car dealer and a computer
     A. The used car dealer knows he's lying.

   This reflects the widespread hacker belief that salescritters are
   self-selected for stupidity (after all, if they had brains and the
   inclination to use them they'd be making more money programming).
   The term "salesthing" is also common.  Compare <marketroid>,

<salt mines> n. Dense quarters housing large numbers of programmers
   working long hours on grungy projects, with some hope of seeing the
   end of the tunnel in N years.  Noted for their absence of sunshine.
   Compare <playpen>.

<sandbender> [IBM] n. A person involved with silicon lithography and
   the physical design of chips.  Compare <ironmonger>, <polygon

<say> v. In some contexts, to type to a terminal.  "To list a
   directory verbosely, you have to say `ls -l'". Tends to imply
   a carriage-return-terminated command (a `sentence').  A computer
   may also be said to `say' things to you even if it doesn't have a
   speech synthesizer, by displaying them on a terminal in response to
   your commands.  Hackers find it odd that this usage confuses other

<SCIENCE-FICTION FANDOM> n. Another voluntary subculture having a very
   heavy overlap with hackerdom; most hackers read SF and/or fantasy
   fiction avidly, and many go to "cons" (SF conventions) or are
   involved in fandom-connected activities like the Society for
   Creative Anachronism.  Some hacker slang originated in SF fandom;
   see <defenestration>, <great-wall>, <cyberpunk>, <h infix>, <ha ha
   only serious>, <IMHO>, <mundane>, <neep-neep>, <Real Soon Now>.
   Additionally, the jargon terms <cowboy>, <cyberspace>, <de-rez>,
   <go flatline>, <ice>, <virus>, <wetware>, <wirehead> and <worm>
   originated in SF itself.

<scratch> [from "scratchpad"] 1. adj. A device or recording medium
   attached to a machine for testing or temporary-use purposes; one
   which can be <SCRIBBLED> on without loss.  Usually in the combining
   forms "scratch memory", "scratch disk", "scratch tape",
   "scratch volume".  See <scratch monkey>. 2. [primarily IBM] v. To
   delete (as in a file).

<scratch monkey> n. As in, "Before testing or reconfiguring, always
   mount a". A proverb used to advise caution when dealing with
   irreplaceable data or devices.  Used in memory of Mabel, the
   Swimming Wonder Monkey who expired when a computer vendor PM'd a
   machine which was regulating the gas mixture that the monkey was
   breathing at the time.  See Appendix A.  See <scratch>.

<screw> [MIT] n. A <lose>, usually in software.  Especially used for
   user-visible misbehavior caused by a bug or misfeature.

<screwage> /scroo'@j/ n. Like <lossage> but connotes that the failure
   is due to a designed-in misfeature rather than a simple inadequacy
   or mere bug.

<scrog> /skrog/ [Bell Labs] v. To damage, trash or corrupt a data
   structure.  "The cblock got scrogged."  Also reported as
   "skrog", and ascribed to "The Wizard of Id" comix.  Equivalent
   to <scribble> or <mangle>

<scrozzle> /skroh'zl/ v. Used when a self-modifying code segment runs
   incorrectly and corrupts the running program, or vital data.  "The
   damn compiler scrozzled itself again!"

<scribble> n. To modify a data structure in a random and
   unintentionally destructive way. "Bletch! Somebody's
   disk-compactor program went berserk and scribbled on the i-node
   table." "It was working fine until one of the allocation routines
   scribbled on low core."  Synonymous with <trash>; compare <mung>,
   which conveys a bit more intention, and <mangle>, which is more
   violent and final.

SCSI /ess see ess ie/ n. Small Computer System Interface is a
   system-level interface between a computer and intelligent devices.
   Typically annotated in literature with "sexy" (/sek'see/) and
   "scuzzy" (/skuhz'zee/) as pronunciation guides...the latter being
   the predominating form, much to the dismay of the designers and
   marketing people.

<search-and-destroy mode> n. Hackerism for the search-and-replace
   facility in an editor, so called because an incautiously chosen
   match pattern can cause <infinite> damage.

<second-system effect> n. When designing the successor to a relatively
   small, elegant and successful system, there is a tendency to become
   grandiose in one's success and perpetrate an <elephantine>
   feature-laden monstrosity.  The term was first used by Fred Brooks
   in his classic book "The Mythical Man-Month". It described the
   jump from a set of nice, simple, operating monitors on the IBM 70xx
   series to OS/360 on the 360 series.

<segfault> n.,v. Syn for <segment>, <seggie>.

<seggie> /seg'ee/ [UNIX] n. Shorthand for <segmentation fault>
   reported from Britain.

<segment> /seg'ment/ v. To experience a <segmentation fault>.
   Confusingly, this is often accented on the first syllable rather
   than on the second as for mainstream v. segment; this is because
   it's actually a noun shorthand that has been verbed.

<segmentation fault (or violation)> n. [UNIX] 1. Error in which a
   running program attempts to access memory not allocated to it and
   <core dump> with a segment violation error.  2. To lose a train of
   thought or a line of reasoning.  Also uttered as an exclamation at
   the point of befuddlement.

<self-reference> n. See <self-reference>.

<selvage> /selv'@j/ [from sewing] n. See <chad> (sense #1).

<semi> /se'mee/ 1. n. Abbreviation for "semicolon", when speaking.
   "Commands to <grind> are prefixed by semi-semi-star" means that
   the prefix is ";;*", not 1/4 of a star.  2. Prefix with words
   such as "immediately", as a qualifier.  "When is the system
   coming up?"  "Semi-immediately." (That is, maybe not for an
   hour).  "We did consider that possibility semi-seriously."  See
   also <infinite>.

<server> n. A kind of <daemon> which performs a service for the
   requester, which often runs on a computer other than the one on
   which the server runs.  A particularly common term on the Internet,
   which is rife with "name servers" "domain servers" "news
   servers" "finger servers" and the like.

<SEX> [Sun User's Group & elsewhere] n. 1.  Software EXchange.  A
   technique invented by the blue-green algae hundreds of millions of
   years ago to speed up their evolution, which had been terribly slow
   up until then.  Today, SEX parties are popular among hackers and
   others. 2. The rather Freudian mnemonic often used for Sign Extend,
   a machine instruction found in many architectures.  Amusingly, the
   Intel 8048 (the microcontroller used in IBM PC keyboards) was
   missing straight SEX but had logical-or and logical-and
   instructions ORL and ANL.

<shareware> n. <freeware> for which the author requests some payment,
   usually in the accompanying documentation files or in an
   announcement made by the software itself.  Such payment may or may
   not buy additional support or functionality.  See <guiltware>,

<shelfware> n. Software purchased on a whim (by an individual user) or
   in accordance with policy (by a corporation or government) but not
   actually required for any particular use.  Therefore, it often ends
   up on some shelf.

<shell> [UNIX, now used elsewhere] n. 1. The command interpreter used
   to pass commands to an operating system.  2. More generally, any
   interface program which mediates access to a special resource or
   <server> for convenience, efficiency or security reasons; for this
   meaning, the usage is usually "a shell around" whatever.  This
   sort of program is also called a "wrapper".

<shell out> [UNIX] n. To spawn an interactive subshell from within a
   program such as a mailer or editor.  "Bang foo runs foo in a
   <subshell>, while bang alone shells out."

<shift left (or right) logical> [from any of various machines'
   instruction sets] 1. v. To move oneself to the left (right).  To
   move out of the way.  2. imper. "Get out of that (my) seat!  You
   can move to that empty one to the left (right)."  Usage: often
   used without the "logical", or as "left shift" instead of
   "shift left".  Sometimes heard as LSH (lish), from the PDP-10
   instruction set.

<shitogram> /shit'oh-gram/ n. A *really* nasty piece of email.
   Compare <nastygram>, <flame>.

<shriek> See <excl>.  Occasional CMU usage, also in common use among
   mathematicians, especially category theorists.

<sig block> /sig blok/ [UNIX; often written ".sig" there] n. Short
   for "signature", used specifically to refer to the electronic
   signature block which most UNIX mail- and news-posting software
   will allow you to automatically append to outgoing mail and news.
   The composition of one's sig can be quite an art form, including an
   ASCII logo or one's choice of witty sayings (see <sig quote>); but
   many consider large sigs a waste of <bandwidth>, and it has been
   observed that the size of one's sig block is usually inversely
   proportional to one's longevity and level of prestige on the net.

<sig quote> /sig kwoht/ [USENET] n. A maxim, quote, proverb, joke or
   slogan embedded in one's <SIG> and intended to convey something of
   one's philosophical stance, pet peeves, or sense of humor. "He
   *must* be a Democrat --- he posted a sig quote from Dan

<silicon> n. Hardware, esp.  ICs or microprocessor-based computer
   systems (compare <iron>). Contrasted with software.

<silly walk> [from Monty Python] v. A ridiculous procedure required to
   accomplish a task.  Like <grovel>, but more <random> and humorous.
   "I had to silly-walk through half the /usr directories to find the
   maps file."

<silo> n. The FIFO input-character buffer in an RS-232 line card.  So
   called from DEC terminology used on DH and DZ line cards for the
   VAX and PDP-11.

<Silver Book> n. Jensen & Wirth's infamous `Pascal User Manual
   and Report', so called because of the silver cover of the
   widely-distributed Springer-Verlag second edition of 1978 (ISBN
   0-387-90144-2). See <Red Book>, <Green Book>, <Blue Book>, <White
   Book>, <Purple Book>, <Orange Book>, <Pink-Shirt Book>, <Dragon
   Book>, <Aluminum Book>

<sitename> [UNIX/Internet] n. The unique electronic name of a computer
   system, used to identify it in UUCP mail, USENET or other forms of
   electronic information interchange.  The folklore interest of
   sitenames stems from the creativity and humor they often display.
   Interpreting a sitename is not unlike interpreting a vanity license
   plate; one has to mentally unpack it, allowing for mono-case and
   length restrictions and the lack of whitespace.  Hacker tradition
   deprecates dull, institutional-sounding names in favor of punchy,
   humorous and clever coinages (except that it is considered
   appropriate for the official public gateway machine of an
   organization to bear the organization's name or acronym).
   Mythological references, cartoon characters, animal names, and
   allusions to SF or fantasy literature are probably the most popular
   sources for sitenames (in roughly that order). See also <network

<skulker> n. Syn. <prowler>.

<slap on the side> adj. A type of external expansion marketed by
   computer manufacturers (e.g. Commodore for their Amiga 500/1000
   series). Various SOTS boxes provided necessities such as memory,
   hard drive controllers, and "conventional" expansion slots.

<sleep> v. On a timesharing system, a process which relinquishes its
   claim on the scheduler until some given event occurs or a specified
   time delay elapses is said to `go to sleep'.

<slim> n. A small, derivative change (e.g. to code).

<slop> n. 1. A one-sided <fudge factor>, that is, an allowance for
   error but only in one of two directions.  For example, if you need
   a piece of wire ten feet long and have to guess when you cut it,
   you make very sure to cut it too long, by a large amount if
   necessary, rather than too short by even a little bit, because you
   can always cut off the slop but you can't paste it back on again.
   When discrete quantities are involved, slop is often introduced to
   avoid the possibility of a <fencepost error>.  2. n. The ratio of
   the size code generated by a compiler to the size of equivalent
   <hand-hacked> assembler code, minus 1; i.e., the space (or maybe
   time) you lose because you didn't do it yourself.  This number is
   often used as a measure of the goodness of a compiler; slop below
   5% is very good, and 10% is usually acceptable for most purposes.
   With modern compiler technology, esp. on RISC machines, the
   compiler's slop may actually be *negative*; that is, humans
   may be unable to generate code as good.  This is one of the reasons
   assembler programming is no longer common.

<slopsucker> n. A lowest-priority task that must wait around until
   everything else has "had its fill" of machine resources.  Only
   when the machine would otherwise be idle is the task allowed to
   "suck up the slop."  Also called a <hungry puppy>.  One common
   variety of slopsucker hunts for large prime numbers.  Compare

<sluggy> /sluh'gee/ adj. Hackish variant of `sluggish'. Used only of
   people, esp.  someone just waking up after a long <gronk out>.

<slurp> v. To read a large data file entirely into core before working
   on it (This may be contrasted with the strategy of reading a small
   piece at a time, processing it, and then reading the next piece).
   "This program slurps in a 1K-by-1K matrix and does an FFT."

<smart> adj. Said of a program that does the <Right Thing> in a wide
   variety of complicated circumstances.  There is a difference
   between calling a program smart and calling it intelligent; in
   particular, there do not exist any intelligent programs (yet).
   Compare <robust> (smart programs can be <brittle>).

<smart terminal> n. A terminal that has enough computing capability to
   perform useful work independently of the main computer.  The
   development of workstations and personal computers has made this
   term and the product it describes semi-obsolescent, but one may
   still hear variants of the phrase "act like a smart terminal"
   used to describe the behavior of workstations/PCs with respect to
   programs that execute almost entirely out of a remote <server>'s
   storage, using said devices as displays.

   There's a classic quote from Rob Pike (inventor of the <blit>
   terminal): "A smart terminal is not a smart*ass* terminal,
   but rather a terminal you can educate."  This illustrates a common
   design problem; the attempt to make peripherals (or anything else)
   intelligent sometimes results in finicky, rigid "special
   features" that become just so much dead weight if you try to use
   the device in any way the designer didn't anticipate.  Flexibility
   and programmability, on the other hand, are *really* smart.

<smash case> v. To lose or obliterate the uppercase/lowercase
   distinction in text input.  "MS-DOS will automatically smash case
   in the filename you give when you create one".

<smash the stack> [C programming] n. On many C implementations it is
   possible to corrupt the execution stack by writing past the end of
   an array declared auto in a routine.  Code that does this is said
   to `smash the stack', and can cause return from the routine to jump
   to a random text address.  This can produce some of the most
   insidious data-dependent bugs known to mankind.  Variants include
   `trash the stack', `<scribble> the stack', `<mangle> the stack';
   `<mung> the stack' is not used as this is never done intentionally.
   See <spam>; see also <aliasing bug>, <fandango on core>, <memory
   leak>, <precedence lossage>, <overrun screw>.

<smiley> n. See <emoticon>.

<smoke test> n. 1. A rudimentary form of testing applied to electronic
   equipment following repair or reconfiguration in which AC power is
   applied and during which the tester checks for sparks, smoke, or
   other dramatic signs of fundamental failure.  2. By extension, the
   first run of a piece of software after construction or a critical
   change.  See <magic smoke>.

<smoking clover> [ITS] n. A <display hack> originally due to Bill
   Gosper.  Many convergent lines are drawn on a color monitor in AOS
   mode (so that every pixel struck has its color incremented).  The
   color map is then rotated.  The lines all have one endpoint in the
   middle of the screen; the other endpoints are spaced one pixel
   apart around the perimeter of a large square.  This results in a
   striking, rainbow-hued, shimmering four-leaf clover.  Gosper joked
   about keeping it hidden from the FDA lest it be banned.

<SMOP> /smop/ [Simple (or Small) Matter of Programming] n. 1. A piece
   of code, not yet written, whose anticipated length is significantly
   greater than its complexity.  Usage: used to refer to a program
   that could obviously be written, but is not worth the trouble.  It
   is also used ironically to imply that a difficult problem can be
   easily solved because a program can be written to do it; the irony
   is that it is very clear that writing such a program will be a
   great deal of work.  Example: "It's easy to change a FORTRAN
   compiler to compile COBOL as well; it's just a SMOP."  2. Often
   used ironically by the intended victim when a suggestion for a
   program is made which seems easy to the suggester, but is obviously
   a lot of work to the programmer.

<snail-mail> n. Paper mail, as opposed to electronic.  Sometimes
   written as the single word `SnailMail'.  Derives from earlier
   coinage `USnail' for which there have been parody posters and
   stamps made.  Oppose <email>.

<snarf> /snarf/ v. 1. To grab, esp. a large document or file for the
   purpose of using it either with or without the author's permission.
   See <BLT>.  Variant: "snarf down", to snarf, sometimes with the
   connotation of absorbing, processing, or understanding.  "I think
   I'll snarf down the list of DDT commands so I'll know what's
   changed recently."  2. [in the UNIX community] to fetch a file or
   set of files across a network.  See also <blast>.

<snarf & barf> /snarf-n-barf/ n. The act of grabbing a region of text
   using a <WIMP> environment and then stuffing the contents of that
   region into another region or into the same region, to avoid
   re-typing a command line.

<snark> [Lewis Carroll, via the Michigan Terminal System] n. 1. A
   system failure.  When a user's process bombed, the operator would
   get a message "Help, Help, Snark in MTS!".  2. More generally,
   any kind of unexplained or threatening event on a computer.  Often
   used to refer to events or log file entries which might indicate an
   attempted security violation.  3. UUCP name of,
   home site of the Jargon File 2.x.x versions.

<sneakernet> n. Term used (generally with ironic intent) for transfer
   of electronic information by physically carrying tape, disks, or
   some other media from one machine to another.  "Never
   underestimate the bandwidth of a station wagon filled with magtape,
   or a 747 filled with CD-ROMs."  Also called "Tennis-Net",

<sniff> v.,n. Synonym for POLL.

<S.O.> /ess-oh/ n. Acronym for Significant Other, almost invariably
   written abbreviated and pronounced "ess-oh" by hackers.  In fact
   the form without periods "SO" is most common.  Used to refer to
   one's primary relationship, esp. a live-in to whom one is not
   married.  See <MOTAS>, <MOTOS>, <MOTSS>.

<softcopy> n. [by analogy with `hardcopy'] A machine readable form of
   corresponding hardcopy.  See <bits>.

<software bloat> n.  The results of <second system effect>.  Commonly
   cited examples include `ls(1)', <X>, <BSD>, <Missed'em-five> and

<software rot> n. (Also known as <bit decay>, <bit rot>) Hypothetical
   disease the existence of which has been deduced from the
   observation that unused programs or features will often stop
   working after sufficient time has passed, even if "nothing has
   changed".  The theory explains that bits decay as if they were
   radioactive.  As time passes, the contents of a file or the code in
   a program will become increasingly garbled.

   There actually are physical processes that produce such effects
   (the alpha particles such as are found in cosmic rays can change
   the contents of a computer memory unpredictably, and various kinds
   of subtle media failures can corrupt files in mass storage) but
   they are quite rare.

   More commonly, "software rot" strikes when a program's
   assumptions become out of date.  If the design was insufficiently
   <robust> it may fail in mysterious ways.  For example, due to
   endemic shortsightedness in the design of COBOL programs, most will
   succumb to software rot when their two-digit year counters wrap
   around at the beginning of the year 2000.

   Historical note: software rot in an even funnier sense than the
   mythical one was a real problem on early research computers (e. g.
   the R1, see <grind crank>).  If a program that depended on a
   peculiar instruction hadn't been run in quite a while, the user
   might discover that the opcodes no longer did the things as they
   used to.  ("Hey, so-and-so needs an instruction to do
   such-and-such.  We can snarf this one, right?  No one uses it.")

<softwarily> /soft-weir'i-lee/ adv.  In a way pertaining to software.
   "The system is softwarily unreliable."  The adjective
   "softwary" is *not* used.  See <hardwarily>.

<some random X> adj. Used to indicate a member of class X, with the
   implication that the particular X is interchangeable with most
   other Xs in whatever context was being discussed. "I think some
   random cracker tripped over the guest timeout last night."

<sorcerer's apprentice mode> n. A bug in a protocol where, under some
   circumstances, the receipt of a message causes more than one
   message to be sent, each of which, when received, triggers the same
   bug.  Used esp. of such behavior caused by <bounce message> loops
   in <email> software.  Compare <broadcast storm>.

<SOS> n.,obs. /ess-oh-ess/ 1. An infamously <losing> text editor.
   Once, back in the 1960's, when a text editor was needed for the
   PDP-6, a hacker crufted togrther a quick-and-dirty "stopgap
   editor" to be used until a better one was written.  Unfortunately,
   the old one was never really discarded when new ones (in
   particular, <TECO>) came along.  SOS is a descendant of that
   editor; SOS means "Son of Stopgap", and many PDP-10 users gained
   the dubious pleasure of its acquaintance.  Since then other
   programs similar in style to SOS have been written, notably BILOS
   (bye'lohss) the Brother-In-Law Of Stopgap. See also <TECO>.  2.
   /sahss/ n. Inverse of <AOS>, from the PDP-10 instruction set.

<space-cadet keyboard> n. The Knight keyboard, a now-legendary device
   used on MIT LISP machines which inspired several still-current
   slang terms and influenced the design of <EMACS>.  It was inspired
   by the Stanford keyboard and equipped with no less than
   *seven* shift keys: four keys for <bucky bits> (`control',
   `meta', `hyper', and `super') and three like the regular shift key,
   called `shift', `top', and `front'.  Many keys have three symbols
   on them: a letter and a symbol on the top, and a Greek letter on
   the front.  For example, the "L" key has an "L" and a two-way
   arrow on the top, and the Greek letter lambda on the front.  If you
   press this key with the right hand while playing an appropriate
   "chord" with the left hand on the shift keys, you can get the
   following results:

     L lower-case "l"
     shift-L upper-case "L"
     front-L Greek lower-case lambda
     front-shift-L Greek upper-case lambda
     top-L two-way arrow (front and shift are ignored)

   And of course each of these may also be typed with any combination
   of the control, meta, hyper, and super keys.  On this keyboard you
   can type over 8000 different characters!  This allows the user to
   type very complicated mathematical text, and also to have thousands
   of single-character commands at his disposal.  Many hackers were
   actually willing to memorize the command meanings of that many
   characters if it will reduce typing time (this view rather
   obviously shaped the interface of EMACS).  Other hackers, however,
   thought having that many bucky bits is overkill, and object that
   such a keyboard can require three or four hands to operate.  See
   <bucky bits>, <cokebottle>, <meta bit>.

<SPACEWAR> n. A space-combat simulation game first implemented on the
   PDP-1 at MIT in 1960-61. SPACEWAR aficionados formed the core of
   the early hacker culture at MIT. Ten years later a descendant of
   the game motivated Ken Thompson to build, in his spare time on a
   scavenged PDP-7, the operating system that became <UNIX>. Ten years
   after that, SPACEWAR was commercialized as one of the first video
   games; descendants are still feeping in video arcades everywhere.

<spaghetti code> n. Describes code with a complex and tangled control
   structure, esp. one using many GOTOs, exceptions or other
   `unstructured' branching constructs.  Pejorative.  The synonym
   "kangaroo code" has been reported.

<spaghetti inheritance> n. [Encountered among users of object-oriented
   languages that use inheritance, such as Smalltalk] A convoluted
   class-subclass graph, often resulting from carelessly deriving
   subclasses from other classes just for the sake of reusing their
   code.  Coined in a (successful) attempt to discourage such
   practice, through guilt by association with <spaghetti code>.

<spam> [from the <MUD> community] v. To crash a program by overrunning
   a fixed-size buffer with excessively large input data.  See also
   <overrun screw>, <smash the stack>.

<spell> n. Syn. <incantation>.

<spiffy> /spi'fee/ adj. 1. Said of programs having a pretty, clever or
   exceptionally well-designed interface. "Have you seen the spiffy X
   version of <empire> yet?" 2. Said sarcastically of programs which
   are perceived to have little more than a flashy interface going for
   them.  Which meaning should be drawn depends delicately on tone of
   voice and context.

<spin> v. Equivalent to <buzz>.  More common among C and UNIX

<spin-lock> [Cambridge] n. A <busy-wait>.  Preferred in Britain.

<splat> n. 1. Name used in many places (DEC, IBM, and others) for the
   ASCII asterisk ("*") character.  2. [MIT] Name used by some
   people for the ASCII number-sign ("#") character.  3. [Stanford]
   Name used by some people for the Stanford/ITS extended ASCII
   circle-x character.  (This character is also called "circle-x",
   "blobby", and "frob", among other names.)  4. [Stanford] Name
   for the semi-mythical extended ASCII circle-plus character.  5.
   Canonical name for an output routine that outputs whatever the
   local interpretation of splat is.  5. [Rochester Institute of
   Technology] The command key on a Macintosh.  Usage: nobody really
   agrees what character "splat" is, but the term is common.

<spooge> /spooj/ 1. n. Inexplicable or arcane code, or random and
   probably incorrect output from a computer program.  2. v. To
   generate code or output as in definition 1.

<spool> [fr. early IBM "Simultaneous Peripheral Operation Off-Line",
   but this acronym is widely thought to have been contrived for
   effect] v. To send files to some device or program (a `spooler')
   that queues them up and does something useful with them later.  The
   spooler usually understood is the `print spooler' controlling
   output of jobs to a printer, but the term has been used in
   connection with other peripherals (especially plotters and graphics

<stack> n. A person's stack is the set of things he has to do in the
   future.  One speaks of the next project to be attacked as having
   risen to the top of the stack.  "I'm afraid I've got real work to
   do, so this'll have to be pushed way down on my stack."  "I
   haven't done it yet because every time I pop my stack something new
   gets pushed."  If you are interrupted several times in the middle
   of a conversation, "my stack overflowed" means "I forget what we
   were talking about" (the implication is that too many items were
   pushed onto the stack than could be remembered, and so the least
   recent items were lost).  The usual physical example of a stack is
   to be found in a cafeteria: a pile of plates sitting on a spring in
   a well in a cart, so that when you put a plate on the top they all
   sink down, and when you take one off the top the rest spring up a
   bit.  See also <PUSH> and <POP>.

   At MIT, all the <stack> usages used to be more commonly found with
   <pdl>, and this may still be true.  Everywhere else <stack> seems
   to be the preferred term.

<stack puke> n. Some micros are said to "puke their guts onto the
   stack" to save their internal state during exception processing.
   On a pipelined machine this can take a while (up to 92 bytes for a
   bus fault on the 68020, for example).

<stale pointer bug> n. Synonym for <aliasing bug> used esp. among
   microcomputer hackers.

<state> n. Condition, situation.  "What's the state of your latest
   hack?"  "It's winning away."  "The system tried to read and
   write the disk simultaneously and got into a totally wedged
   state."  A standard question is "What's your state?" which means
   "What are you doing?" or "What are you about to do?"  Typical
   answers might be "I'm about to gronk out", or "I'm hungry".
   Another standard question is "What's the state of the world?"
   meaning "What's new?" or "What's going on?". The more terse and
   humorous way of asking these conventions would be "State-p?".

<stiffy> [ULowell] n. 3.5" <microfloppies>, so called because their
   jackets are more firm than the 5.25" and 8" floppy.

<stir-fried random> alt. <stir-fried mumble> n. Term used for frequent
   best dish of those hackers who can cook.  Consists of random fresh
   veggies and meat wokked with random spices.  Tasty and economical.
   See <random>, <great-wall>, <ravs>, <ORIENTAL FOOD>; see also

<stomp on> v.  To inadvertently overwrite something important, usually
   automatically.  Example: "All the work I did this weekend got
   stomped on last night by the nightly-server script."  Compare
   <scribble>, <mangle>, <trash>, <scrog>, <roach>.

<stoppage> /sto'p@j/ n. Extreme lossage (see <lossage>) resulting in
   something (usually vital) becoming completely unusable.  "The
   recent system stoppage was caused by a <fried> transformer."

<stubroutine> /stuhb'roo-teen/ [contr. of "stub routine"] n. Tiny,
   often vacuous placeholder for a subroutine to be written or fleshed
   out later.

<stunning> adj. Mind-bogglingly stupid.  Usually used in sarcasm.
   "You want to code *what* in ADA? That's...a stunning idea!"
   See also <non-optimal solution>.

<subshell> [UNIX, MS-DOS] n. An OS command interpreter (see <shell>)
   spawned from within a program, such that exit from the command
   interpreter returns one to the parent program in a state that
   allows it to continue execution.  Oppose <chain>.

<sucking mud> [Applied Digital Research] adj.  Crashed or wedged.
   Usually said of a machine that provides some service to a network,
   such as a file server.  This Dallas regionalism derives from the
   East Texas oil field lament, "Shut 'er down, Ma, she's a-suckin'
   mud."  Often used as a query.  "We are going to reconfigure the
   network, are you ready to suck mud?"

<suit> n. 1. Ugly and uncomfortable `business clothing' often worn by
   non-hackers.  Invariably worn with a `tie', a strangulation device
   which partially cuts off the blood supply to the brain.  It is
   thought that this explains much about the behavior of suit-
   wearers. 2. A person who habitually wears suits, as distinct from a
   techie or hacker.  See <loser>, <burble> and <brain-damaged>.
   English, BTW, is relatively kind; our Soviet correspondent informs
   us that the corresponding idiom in Russian hacker jargon is
   `sovok', lit. a tool for grabbing garbage.

<sunspots> n. Notional cause of an odd error. "Why did the program
   suddenly turn the screen blue?" "Sunspots, I guess".  Also cause
   of bitrot, from the genuine, honest-to-god fact that sunspots will
   increase cosmic radiation which can flip single bits in memory.
   Needless to say, although real sunspot errors happen, they are
   extremely rare.  See <cosmic rays>, <phase of the moon>.

<sun-stools> n. Unflattering hackerism for SunTools, a pre-X windowing
   environment notorious in its day for size, slowness and misfeatures
   (X, however, is larger and slower; see <second-system effect>).

<SUPDUP> /soop'doop/ v. To communicate with another ARPAnet host using
   the SUPDUP program, which is a SUPer-DUPer <TELNET> talking a
   special display protocol used mostly in talking to ITS sites.
   Sometimes abbreviated to SD.

<superprogrammer> n.  A prolific programmer; one who can code
   exceedingly well and quickly.  Not all hackers are
   superprogrammers, but many are.  (Productivity can vary from one
   programmer to another by factors of as much as 1000.  For example,
   programmer A might be able to write an average of 3 lines of
   working code in one day, while another, with the proper tools and
   skill, might be able to write 3,000 lines of working code in one
   day.  This variance is astonishing, appearing in very few other
   areas of human endeavor.)  The term superprogrammer is more
   commonly used within such places as IBM than in the hacker
   community.  It tends to stress productivity rather than creativity
   or ingenuity.  Hackers tend to prefer the terms <hacker> and

<Suzie COBOL> /soo'zee koh'bol/ 1. [IBM, prob. fr.  Frank Zappa's
   "little Suzy Creamcheese"] n. A coder straight out of training
   school who knows everything except the benefits of comments in
   plain English.  Also (fashionable among personkind wishing to avoid
   accusations of sexism) `Sammy Cobol' or (in some non-IBM circles)
   `Cobol Charlie'.  2.  [proposed] Meta-name for any <code grinder>,
   analogous to <J. Random Hacker>.

<swab> [From the PDP-11 "byte swap" instruction, and immortalized in
   the option "conv=swab" to <DD>] 1. v. to solve the <NUXI problem>
   by swapping bytes in a file. 2. Also, the program in V7 UNIX used
   to perform this action, or anything functionally equivalent to it.
   See also <big-endian>, <little-endian>, <bytesexual>.

<swap space> n. Storage space. "I'm just using that corner of the
   machine room for swap space".

<swapped> adj. From the older (per-task) method of using secondary
   storage devices to implement support for multitasking.  Something
   which is <swapped in> is available for immediate use in main
   memory, and otherwise is <swapped out>.  Often used metaphorically
   to refer to people's memories ("I read the Scheme Report every few
   months to keep the information swapped in.") or to their own
   availability ("I'll swap you in as soon as I finish looking at
   this other problem.").  Compare <page in>, <page out>.

<swizzle> v. To convert external names or references within a data
   structure into direct pointers when the data structure is brought
   into main memory from external storage; also called "pointer
   swizzling"; the converse operation is sometimes termed

<sync> /sink/ [UNIX] n.,v. 1. To force all pending I/O to the disk.
   2.  More generally, to force a number of competing processes or
   agents to a state that would be `safe' if the system were to crash;
   thus, to checkpoint.  See <flush>.

<syntactic sugar> [coined by Peter Landin] n. Features added to a
   language or formalism to make it `sweeter' for humans, that do not
   affect the expressiveness of the formalism (compare <chrome>). Used
   esp.  when there is an obvious and trivial translation of the
   `sugar' feature into other constructs already present in the
   notation.  Example: C's "a[i]" notation is syntactic sugar for
   "*(a + i)".  "Syntactic sugar causes cancer of the semicolon."
   --- Alan Perlis.

<sys-frog> [the PLATO system] n. Playful hackish variant of
   "sysprog" which is in turn short for "systems-programmer".

<system> n. 1. The supervisor program or OS on a computer.  2. n.  The
   entire computer system, including input/output devices, the
   supervisor program or OS, and possibly other software.  3. Any
   large-scale program.  4. Any method or algorithm.  5. The way
   things are usually done.  Usage: a fairly ambiguous word.  "You
   can't beat the system."  <System hacker>: one who hacks the system
   (in sense 1 only; for sense 2 one mentions the particular program:
   e.g., "lisp hacker")

                                {= T =}

<t> /tee/ 1. [from LISP terminology for "true"] Yes.  Usage: used in
   reply to a question, particularly one asked using the "-P"
   convention).  See NIL.  In LISP, the name T means "true", among
   other things.  Some hackers use "T" and "NIL" instead of
   "yes" and "no" almost reflexively.  This sometimes causes
   misunderstandings.  When a waiter or flight attendant asks whether
   a hacker wants coffee, he may well respond "T", meaning that he
   wants coffee; but of course he will be brought a cup of tea
   instead.  As it happens, most hackers like tea at least as well as
   coffee, particularly those who frequent Chinese restaurants, so
   it's not that big a problem.  2. See <time t>. 3. In
   transaction-processing circles, an abbreviation for the noun
   "transaction". 4. [Purdue] Alternate spelling of <tee>

<tail recursion> n. See <tail recursion>.

<talk mode> n. The state a terminal is in when linked to another via a
   bidirectional character pipe, to support on-line dialogue between
   two or more users.  Talk mode has a special set of jargon words,
   used to save typing, which are not used orally:

     BCNU      Be seeing you.
     BTW       By the way...
     BYE?      Are you ready to unlink?  (This is the standard way to
               end a talk mode conversation; the other person types BYE
               to confirm, or else continues the conversation.)
     CUL       See you later.
     ENQ?      Are you busy? Expects ACK or NAK in return.
     FOO?      A greeting, also meaning R U THERE?  Often used in the
               case of unexpected links, meaning also "Sorry if I
               butted in" (linker) or "What's up?" (linkee).
     FYI       For your information...
     FYA       For your amusement...
     GA        Go ahead (used when two people have tried to type\
               this cedes the right to type to the other).
     HELLOP    A greeting, also meaning R U THERE?  (An instance of the
               "-P" convention.)
     JAM       Just a minute... Equivalent to SEC...
     NIL       No (see the main entry for NIL).
     O         Over to you (lower-case works too).
     OO        Over and out (lower-case works too).
     /         Another form of "Over to you" (from x/y as "x overy y")
     OBTW      Oh, by the way...
     R U THERE?  Are you there?
     SEC       Wait a second (sometimes written SEC...).
     T         Yes (see the main entry for T).
     TNX       Thanks.
     TNX 1.0E6 Thanks a million (humorous).
     WTF       The universal interrogative particle.  WTF knows what
               it means?
     WTH       What the hell?
     <double CRLF> When the typing party has finished, he types two CRLFs
               to signal that he is done; this leaves a blank line between
               individual "speeches" in the conversation, making it easier to
               re-read the preceding text.
     <name>:   When three or more terminals are linked, each speech is
               preceded by the typist's login name and a colon (or a hyphen) to
               indicate who is typing.  The login name often is shortened to a
               unique prefix (possibly a single letter) during a very long
     /\/\/\    A giggle or chuckle (rare).  On a MUD, this almost certainly mean
               `earthquake fault'.

   Most of the above "sub-jargon" is used at both Stanford and MIT.
   Several of these are also common in EMAIL, esp.  FYI, FYA, BTW,
   BCNU, and CUL.  A few other abbreviations have been reported from
   commercial networks such as GEnie and Compuserve where on-line
   `live' chat including more than two people is common and usually
   involves a more `social' context, notably

     <g> grin
     BBL      be back later
     BRB      be right back
     HHOJ     ha ha only joking
     HHOS     <ha ha only serious>
     LOL      laughing out loud
     ROTF     rolling on the floor
     ROTFL    rolling on the floor laughing
     AFK      away from keyboard
     b4       before
     CU l8tr  see you later
     MORF     Male or Female?
     TTFN     ta-ta for now
     OIC      Oh, I see
     rehi     hello again

   These are not used at universities or in the UNIX world;
   conversely, most of the people who know these are unfamiliar with
   FOO?, BCNU, HELLOP, NIL, and T.

   The <MUD> community uses a mixture of USENET/Internet emoticons, a
   few of the more natural of the old-style talk mode abbrevs, and
   some of the `social' list above; specifically, MUD respondents
   report use of BBL, BRB, LOL, b4, BTW, WTF, and WTH.  The use of
   rehi is also common; in fact, mudders are fond of re- compounds and
   will frequently `rehug' or `rebonk' (see <bonk/oif>) people.  The
   verbe `re' by itself is construed as `repeat my last action
   toward'.  In general, though, mudders express a preference for
   typing things out in full rather than using abbreviations; this may
   be due to the relative youth of the MUD cultures, which tend to
   include many touch typists and assume high-speed links.  The
   following uses specific to MUDs are reported:

     UOK?      Are you OK?
     THX       Thanks (mutant of TNX)
     CU l8er   See you later (mutant of CU l8tr)

   See also <hakspek>, <emoticon>, <bonk/oif>.

<tanked> adj. Same as <down>, used primarily by UNIX hackers.  See
   also <hosed>.  Popularized as a synonym for "drunk" by Steve
   Dallas in the late lamented "Bloom County" comics.

<tar and feather> [from UNIX `tar(1)'] v. To create a transportable
   archive from a group of files by first sticking them together with
   the tape archiver `tar(1)' and then compressing the result (see
   <compress>). The latter is dubbed `feathering' by analogy to what
   you do with an airplane propeller to decrease wind resistance;
   smaller files, after all, slip through comm links more easily.

<taste> n. [primarily MIT-DMS] 1. The quality in programs which tends
   to be inversely proportional to the number of features, hacks, and
   kluges programmed into it.  Also, "tasty", "tasteful",
   "tastefulness".  "This feature comes in N tasty flavors."
   Although "tasteful" and "flavorful" are essentially synonyms,
   "taste" and <flavor> are not.  Taste refers to sound judgement on
   the part of the creator; a program or feature can *exhibit*
   taste but cannot "have" taste.  On the other hand, a feature can
   have <flavor>.  Also, <flavor> has the additional meaning of
   "kind" or "variety" not shared by "taste".  <flavor> is a
   more popular word among hackers than "taste", though both are
   used.  2.  Also as <tayste>; two bits.  Compare <crumb>, <dynner>,
   <playte>, <nybble>.

<TCB> /tee see bee/ [IBM] 1. Trouble Came Back.  Intermittent or
   difficult-to reproduce problem which has failed to respond to
   neglect.  Compare <heisenbug>.  Not to be confused with: 2. Trusted
   Computing Base, an "official" jargon term from the <Orange Book>.

<TECO> /tee'koh/ obs. 1. v. Originally, to edit using the TECO editor
   in one of its infinite variations (see below); sometimes still used
   to mean "to edit" even when not using TECO! Usage: rare and now
   primarily historical.  2. [originally an acronym for (paper)
   "Tape Editor and COrrector"; later, "Text Editor and
   Corrector"] n. A text editor developed at MIT, and modified by
   just about everybody.  If all the dialects are included, TECO might
   have been the single most prolific editor in use before <EMACS>
   to which it was directly ancestral.  Noted for its powerful
   programming-language-like features and its incredibly hairy syntax.
   It is literally the case that every possible sequence of ASCII
   characters is a valid, though probably uninteresting, TECO program;
   one common hacker game used to be mentally working out what the
   teco commands corresponding to human names did.  As an example,
   here is a TECO program that takes a list of names like this:

     Loser, J. Random
     Quux, The Great
     Dick, Moby

   sorts them alphabetically according to last name, and then puts the
   last name last, removing the comma, to produce this:

     Moby Dick
     J. Random Loser
     The Great Quux

   The program is:

     [1 J ^P $ L $ $
     J <.-Z; .,(S,$ -D .)FX1 @F^B $K :L I $ G1 L>$$

   (where ^B means "Control-B" (ASCII 0000010) and $ is actually an
   <escape> (ASCII 0011011) character)

   In fact, this very program was used to produce the second, sorted
   list from the first list!  The first hack at it had a <bug>: gls
   (the author) had accidentally omitted the "@" in front of
   "F^B", which as anyone can see is clearly the wrong thing.  It
   worked fine the second time.  There is no space to describe all the
   features of TECO, but it may be of interest that "^P" means
   "sort" and "J <.-Z; ...  L>" is an idiomatic series of commands
   for "do once for every line".

   In 1990, TECO is now pretty much one with the dust of history,
   having been replaced in the affections of hackerdom by <EMACS>.  It
   can still be found lurking on VMS and a couple of crufty PDP-11
   operating systems, however.

<tee> n.,v. [Purdue] A carbon copy of an electronic transmission,
   "Oh, you're sending him the <bits> to that?  Slap on a tee for
   me."  From the UNIX command `tee(1)'.  Can also mean `save one for
   me' as in "Tee a slice for me!". Also spelled `T'.

<Telerat> /tel'@-rat/ n. Unflattering hackerism for "Teleray", a
   line of extremely losing terminals.  See also <terminak>,
   <sun-stools>, <HP-SUX>.

<TELNET> /telnet/ v. To communicate with another ARPAnet host using
   the <TELNET> program.  TOPS-10 people use the word IMPCOM since
   that is the program name for them.  Sometimes abbreviated to TN.
   "I usually TN over to SAIL just to read the AP News."

<ten finger interface> n. The interface between two networks which
   cannot be directly connected for security reasons; refers to the
   practice of placing two terminals side by side and having an
   operator read from one and type into the other.

<tense> adj. Of programs, very clever and efficient.  A tense piece of
   code often got that way because it was highly <bum>med, but
   sometimes it was just based on a great idea.  A comment in a clever
   display routine by Mike Kazar, a student hacker at CMU: "This
   routine is so tense it will bring tears to your eyes.  Much thanks
   to Craig Everhart and James Gosling for inspiring this <hack
   attack>."  A tense programmer is one who produces tense code.

<tenured graduate student> n.  One who has been in graduate school for
   ten years (the usual maximum is five or six): a "ten-yeared"
   student (get it?).  Students don't really get tenure, of course,
   the way professors do, but a tenth-year graduate student has
   probably been around the university longer than any non-tenured

<teraflop club> /ter'a-flop kluhb/ [FLOP = Floating Point Operation]
   n.  Mythical group of people who consume outrageous amounts of
   computer time in order to produce a few simple pictures of glass
   balls with intricate ray tracing techniques.  Cal Tech professor
   James Kajiya is said to have been the founding member.  See also

<terminak> /ter'mi-nak/ [Caltech, ca. 1979] n. Any malfunctioning
   computer terminal.  A common failure mode of Lear-Siegler ADM3a
   terminals caused the "L" key to produce the "K" code instead;
   complaints about this tended to look like "Terminak #3 has a bad
   keyboard.  Pkease fix."  See <sun-stools>, <Telerat>, <HP-SUX>.

<terminal brain death> n. Extreme form of <terminal illness> (sense

<terminal illness> n. 1. Syn. with <raster burn>.  2.  The `burn-in'
   condition your CRT tends to get if you don't have a screen saver.

<terminal junkie> [Great Britain] n. An early <larval stage> hacker
   who spends most of their time wandering the directory tree and
   writing <noddy> programs just to get his/her fix of computer time.
   Variants include "terminal jockey", "console junkie", or <console
   jockey>.  The term "console jockey" seems to imply more expertise
   than the other three.

<terpri> /ter'pree/ [from the LISP 1.5 (and later, MacLISP) function
   to start a new line of output] v. To output a <CRLF>. Now
   rare.  It is a contraction of "TERminate PRInt line".

<TeX> /tekh/ n. An extremely powerful <macro>-based text-formatter
   written by Donald E. Knuth, very popular in the computer-science
   community (it is good enough to have displaced UNIX `troff(1)', the
   other favored formatter, even at many UNIX installations).  TeX
   fans insist on the correct (guttural) pronunciation spelling (all
   caps, with the E depressed below the baseline) of the name (the
   mixed-case "TeX" is considered an acceptable kluge on ASCII-only
   devices).  They like to proliferate names from the word `TeX' ---
   such as TeXnichian (TeX user), TeXhacker (TeX programmer),
   TeXmaster (competent TeX programmer), TeXhax, TeXnique.

<thanks in advance> [USENET] Conventional net.politeness ending a
   posted request for information or assistance.  Sometimes written
   "advTHANKSance". See <net.>, <netiquette>.

<theology> n. 1. Ironically used to refer to <religious issues>.  2.
   Technical fine points of an abstruse nature, esp. those where the
   resolution is of theoretical interest but relatively <marginal>
   with respect to actual use of a design or system.  Used esp. around
   software issues with a heavy AI or language design component.
   Example: the deep- vs. shallow-binding debate in the design of
   dynamically-scoped LISPs.

<theory> n. Used in the general sense of idea, plan, story, or set of
   rules.  This is a generalization and abuse of the technical
   meaning. "What's the theory on fixing this TECO loss?"  "What's
   the theory on dinner tonight?"  ("Chinatown, I guess.")
   "What's the current theory on letting lusers on during the day?"
   "The theory behind this change is to fix the following well-known

<thinko> /thin'ko/ [by analogy with `typo'] n. A bubble in the stream
   of consciousness; a momentary, correctable glitch in mental
   processing, especially one involving recall of information learned
   by rote.  Syn. <braino>.  Compare <mouso>.

<This time, for sure>!  Ritual affirmation frequently uttered during
   protracted debugging sessions involving numerous small obstacles
   (as, in for example, attempts to bring up a UUCP connection). For
   the proper effect, this must be uttered in a fruity imitation of
   Bullwinkle the Moose.  Also heard: "Hey, Rocky! Watch me pull a
   rabbit out of my hat!".  The canonical response is, of course,
   "But that trick *never* works!". See <HUMOR, HACKER>.

<thrash> v. To move wildly or violently, without accomplishing
   anything useful.  Paging or swapping systems which are overloaded
   waste most of their time moving data into and out of core (rather
   than performing useful computation), and are therefore said to
   thrash.  Someone who keeps changing his mind is said to be

<thread> /thred/ n. [USENET, GEnie] Common abbreviation of `topic
   thread', a more or less continuous chain of postings on a single
   topic.  Also in 2. <upthread>: earlier in the discussion. "As Joe
   pointed out upthread..."

<three-finger salute> n. Syn. for <vulcan nerve pinch>.

<thunk> [mythically, the sound made by data when pushed onto the
   stack] n. 1. " ... a piece of coding which which provides an
   address." --- P.Z Ingerman, who invented <thunk>s in 1961 as a way
   of binding actual parameters to their formal definitions in
   Algol-60 procedure calls.  If a procedure is called with an
   expression in the place of a formal parameter, the compiler
   generates a <thunk> to compute the expression and leave the address
   of the result in some standard location such as an index register.
   2. Later generalized into an expression, frozen together with its
   environment for later evaluation if and when needed.  The process
   of unfreezing these <thunk>s is called `forcing'.  3. Stub routine,
   in an overlay programming environment, which loads and jumps to the
   correct overlay.  4. People and activities scheduled in a thunklike
   manner.  "It occurred to me the other day that I am rather
   accurately modelled by a thunk --- I frequently need to be forced
   to completion."  --- paraphrased from a .plan file.

<tick> n. 1. The width of one tick of the system clock on the
   computer.  Often 1 AC cycle time (1/60 second in the U.S. and
   Canada, and 1/50 most other places) but more recently 1/100 sec has
   become common.  Syn <jiffy>.  2. In simulations, the discrete unit
   of time that passes "between" iterations of the simulation
   mechanism.  In AI applications, this amount of time is often left
   unspecified, since the only constraint of interest is that caused
   things happen after their causes.  This sort of AI simulation is
   often pejoratively referred to as "tick-tick-tick" simulation,
   especially when the issue of simultaneity of events with long,
   independent chains of causes is <handwave>d.

<tick-list features> [Acorn Computers] n. Features in software or
   hardware that customers insist on but never use (calculators in
   desktop TSRs and that sort of thing).

<time sink> n. A project which consumes unbounded amounts of time.

<time t> /tiem tee/ n. 1. An unspecified but usually well-understood
   time, often used in conjunction with a later time T+1.  "We'll
   meet on campus at time T or at Louie's at time T+1." means, in the
   context of going out for dinner, "If we meet at Louie's directly,
   we can meet there a little later than if we meet on campus and then
   have to travel to Louie's."  (Louie's is a Chinese restaurant in
   Palo Alto that is a favorite with hackers.  Had the number 30 been
   used instead of "one", it would have implied that the travel time
   from campus to Louie's is thirty minutes; whatever time T is (and
   that hasn't been decided on yet), you can meet half an hour later
   at Louie's than you could on campus and end up eating at the same
   time.  2. "since (or at) time t equals minus infinity": A long time
   ago; for as long as anyone can remember; at the time that some
   particular frob was first designed.  Sometimes the word "time" is
   omitted if there is no danger of confusing "T" as a time with
   "T" meaning "yes".

<tip of the ice-cube> [IBM] n. The visible part of something small and
   insignificant.  Used as an ironic comment in situations where "tip
   of the iceberg" might be appropriate if the subject were actually

<tired iron> [IBM] n. Hardware that is perfectly functional but enough
   behind the state of the art to have been superseded by new
   products, presumably with enough improvement in bang-per-buck that
   the old stuff is starting to look a bit like a <dinosaur>.

<tits on a keyboard> n. Small bumps on certain keycaps to keep
   touch-typists registered.  (Usually on the 5 of a numeric keypad,
   and on F and J of a QWERTY keyboard.)

<TLA> /tee el ay/ [Three-Letter-Acronym] n. 1. Self-describing acronym
   for a species with which computing terminology is infested.  2. Any
   confusing acronym at all.  Examples include MCA, FTP, SNA, CPU,
   MMU, SCCS, DMU, FPU, TLA, NNTP.  People who like this looser usage
   argue that not all TLAs have three letters, just as not all four
   letter words have four letters.  One also hears of "ETLA"
   (Extended Three Letter Acronym, pronounced /ee tee el ay/ ) being
   used to describe four-letter acronyms.

<toast> 1. n. Any completely inoperable system, esp. one that has just
   crashed; "I think BUACCA is toast." 2. v. To cause a system to
   crash accidentally, especially in a manner that requires manual
   rebooting. "Rick just toasted harp again."

<toaster> n. 1. The archetypal really stupid application for an
   embedded microprocessor controller esp. `toaster oven'; often used
   in comments which imply that a scheme is inappropriate technology.
   "<DWIM> for an assembler?  That'd be as silly as running UNIX on
   your toaster!" 2.  A very very dumb computer. "You could run this
   program on any dumb toaster."  See <bitty box>, <toaster>, <toy>.

<toggle> v. To change a BIT from whatever state it is in to the other
   state; to change from 1 to 0 or from 0 to 1.  This probably comes
   from "toggle switches", such as standard light switches, though
   the word "toggle" apparently originally referred to the mechanism
   that keeps the switch in the position to which it is flipped,
   rather than to the fact that the switch has two positions.  There
   are four things you can do to a bit: set it (force it to be 1),
   clear (or zero) it, leave it alone, or toggle it.  (Mathematically,
   one would say that there are four distinct boolean-valued functions
   of one boolean argument, but saying that is much less fun than
   talking about toggling bits.)

<tool> 1. n. A program primarily used to create other programs, such
   as a compiler or editor or cross-referencing program.  Oppose
   <app>, <operating system>. 2. [UNIX] An application program with a
   simple, "transparent" (typically text-stream) interface designed
   specifically to be used in programmed combination with other tools
   (see <filter>).  3. [MIT] v.i. To work; to study.  See <hack>.

<TOPS-10> /tops-ten/ n. DEC's proprietary OS for the fabled <PDP-10>
   machines, long a favorite of hackers but now effectively extinct.
   A fountain of hacker folklore; see Appendix A. See also <ITS>,
   <TOPS-20>, <TWENEX>, <VMS>, <operating system>.  TOPS-10 was
   sometimes called BOTS-10 ("from bottoms-ten") as a comment on the
   inappropriateness of describing it as the top of anything.

<TOPS-20> /tops-twen'tee/ n. See <TWENEX>.

<tourist> [from MIT's ITS system] n. A guest on the system, especially
   one who generally logs in over a network from a remote location for
   games and other trivial purposes.  One step below <luser>.

<touristic> adj. Having the quality of a <tourist>.  Often used as a
   pejorative, as in "losing touristic scum".

<toy> n. A computer system; always used with qualifiers.  1. <nice
   toy>: One which supports the speaker's hacking style adequately.
   2.  <just a toy>: A machine that yields insufficient <computron>s
   for the speaker's preferred uses.  This is not condemnatory as is
   <bitty box>; toys can at least be fun.  See also <Get a real
   computer!>, <bitty box>.

<toy problem> [AI] n. A deliberately simplified or even oversimplified
   case of a challenging problem used to investigate, prototype, or
   test algorithms for the real problem.  Sometimes used pejoratively.
   See also <gedanken>.

<trap> 1. n. A program interrupt, usually used specifically to refer
   to an interrupt caused by some illegal action taking place in the
   user program.  In most cases the system monitor performs some
   action related to the nature of the illegality, then returns
   control to the program.  2. v. To cause a trap.  "These
   instructions trap to the monitor."  Also used transitively to
   indicate the cause of the trap.  "The monitor traps all
   input/output instructions."  This term is associated with
   assembler programming (INTERRUPT is more common among HLL
   programmers) and appears to be fading into history as the role of
   assembler continues to shrink.

<trap door> alt. <trapdoor> n. Syn. with <back door>.

<trash> v. To destroy the contents of (said of a data structure). The
   most common of the family of near-synonyms including <mung>,
   <mangle> and <scribble>.

<tree killer> [Sun] n. 1. A printer.  2. A person who wastes paper.
   This should be interpreted in a broad sense; `wasting paper'
   includes the production of <spiffy> but <content-free> documents.
   Thus, most <suits> are tree-killers.

<trivial> adj. 1. In explanation, too simple to bother detailing. 2.
   Not worth the speaker's time. 3. Complex, but solvable by methods
   so well-known that anyone not utterly <cretinous> would have
   thought of them already.  Hackers' notions of triviality may be
   quite at variance with those of non-hackers.  See <nontrivial>,

<troglodyte> [Commodore] n. 1. A hacker who never leaves his cubicle.
   The term `Gnoll' (from D&D) is also reported.  2. [proposed] A
   curmudgeon attached to an obsolescent computing environment.

<troglodyte mode> [Rice University] n. Programming with the lights
   turned off, sunglasses on, and the (character) terminal inverted
   (black on white) because you've been up for so many days straight
   that your eyes hurt.  Loud music blaring from a stereo stacked in
   the corner is optional but recommended.  See <larval stage>,

<trojan horse> [coined by MIT-hacker-turned-spook Dan Edwards] n. A
   program designed to break security or damage a system that is
   disguised as something else benign, such as a directory lister or
   archiver.  See <virus>, <worm>.

<true-hacker> [analogy with "trufan" from SF fandom] n.  One who
   exemplifies the primary values of hacker culture, esp.  competence
   and helpfulness to other hackers.  A high complement.  "He spent
   six hours helping me bring up UUCP and netnews on my FOOBAR 4000
   last week --- unequivocally the act of a true-hacker."  Compare
   <demigod>, oppose <munchkin>.

<tty> /tee-tee-wie/ [UNIX], /ti'tee/ [ITS, but some UNIX people say it
   this way as well] n. 1. Terminal of the teletype variety,
   characterized by a noisy mechanical printer, a very limited
   character set, and poor print quality.  Usage: antiquated (like the
   TTYs themselves).  2.  [especially UNIX] Any terminal at all;
   sometimes used to refer to the particular terminal controlling a
   given job.

<tube> n. A CRT terminal.  Never used in the mainstream sense of TV;
   real hackers don't watch TV, except for Loony Toons and Rocky &
   Bullwinkle and the occasional cheesy old swashbuckle movie.

<tunafish> n. In hackish lore, refers to the mutated punchline of an
   age-old joke to be found at the bottom of the man pages of
   `tunefs(8)' in the original <BSD> 4.2 distribution.  The joke
   was removed in later releases once commercial sites started
   developing 4.2. Tunefs relates to the `tuning' of file-system
   parameters for optimum performance, and at the bottom of a few
   pages of <black art> writings was a BUGS section consisting of the
   line "You can tune a filing system, but you can't tunafish."

<tune> [from automotive or musical usage] v. To optimize a program or
   system for a particular environment, esp. by adjusting numerical
   parameters designed as <hook>s for tuning, e.g. by changing #define
   lines in C.  One may `tune for time' (fastest execution) `tune for
   space' (least memory utilization) or `tune for configuration' (most
   efficient use of hardware). See <bum>, <hot spot>, <hand-hacking>.

<tweak> v. 1. To change slightly, usually in reference to a value.
   Also used synonymously with <twiddle>.  If a program is almost
   correct, rather than figuring out the precise problem, you might
   just keep tweaking it until it works.  See <frobnicate> and <fudge
   factor>.  2. To <tune> or <bum> a program.  This is preferred usage
   in England.

<TWENEX> /twe-neks/ n. The TOPS-20 operating system by DEC.  TOPS-10
   was a typically crufty DEC operating system for the PDP-10, so
   TOPS-20 was the obvious name choice for the DEC-20 OS. Bolt,
   Beranek and Newman (BBN) had developed their own system, called
   <TENEX> (TEN EXecutive), and in creating TOPS-20 DEC copied TENEX
   and adapted it for the 20. The term TWENEX was therefore a
   contraction of "twenty TENEX".  DEC people cringed when they
   heard TOPS-20 referred to as "TWENEX", but the term caught on
   nevertheless.  The written abbreviation "20x" was also used.
   TWENEX was successful and very popular; in fact, there was a period
   in the 1980s when it commanded almost as fervent a culture of
   partisans as UNIX or ITS --- but DEC's decision to scrap all the
   internal rivals to the VAX architecture and the relatively stodgy
   VMS OS killed the DEC-20 and put a sad end to TWENEX's brief day in
   the sun.

<twiddle> n. 1. tilde (ASCII 176, "~").  Also called "squiggle",
   "sqiggle" (sic---pronounced "skig'gul"), and "twaddle", but
   twiddle is by far the most common term.  2. A small and
   insignificant change to a program.  Usually fixes one bug and
   generates several new ones.  3. v. To change something in a small
   way.  Bits, for example, are often twiddled.  Twiddling a switch or
   knob implies much less sense of purpose than toggling or tweaking
   it; see <frobnicate>.  To speak of twiddling a bit connotes
   aimlessness, and at best doesn't specify what you're doing to the
   bit; by contrast, toggling a bit has a more specific meaning (see

<twink> /twink/ [UCSC] n. Equivalent to <read-only user>.

<two-to-the-n> q.  Used like N, but referring to bigger numbers. "I
   have two to the N things to do before I can go out for lunch"
   means you probably won't show up.

<two-pi> q. The number of years it takes to finish one's thesis.
   Occurs in stories in the form: "He started on his thesis; two pi
   years later...".

<twonkie> n. The software equivalent of a Twinkie; a useless
   "feature" added to look sexy and placate a <marketroid>.

                                {= U =}

<UBD> [abbreviation for "User Brain Damage"] An abbreviation used to
   close out trouble reports obviously due to utter cluelessness on
   the user's part.  Compare <PBD>; see also <brain-damaged>.

<undefined external reference> excl. [UNIX] Message from UNIX's
   linker.  Used to indicate loose ends in an argument or discussion.

<under the hood> prep. [hot-rodder talk] 1. Used to introduce the
   underlying implementation of a product (hardware, software, or
   idea). Implies that the implementation is not intuitively obvious
   from the appearance, but the speaker is about enable the listener
   to <zen> it. "Let's now look under the hood to see how ..."  2.
   Can also imply that the implementation is much simpler than the
   appearance would indicate, as in "Under the hood, we are just
   fork/execling the shell."  3. Inside a chassis, as in "Under the
   hood, this baby has a 40MHz 68030!"

<uninteresting> adj. 1. Said of a problem which, while <nontrivial>,
   can be solved simply by throwing sufficient resources at it. 2.
   Also said of problems for which a solution would neither advance
   the state of the art nor be fun to design and code.  True hackers
   regard uninteresting problems as an intolerable waste of time, to
   be solved (if at all) by lesser mortals.  See <WOMBAT>, <SMOP>;
   oppose <interesting>.

<UN*X> n. Used to refer to the Unix operating system (trademark and/or
   copyright AT&T) in writing, but avoiding the need for the ugly (tm)
   typography.  Also used to refer to any or all varieties of Unixoid
   operating systems.  Ironically, lawyers now say (1990) that the
   requirement for superscript-tm has no legal force, but the asterisk
   usage is entrenched anyhow.  It has been suggested that there may
   be a psychological connection to practice in certain religions
   where the name of the deity is never written out in full, e.g. JHWH
   or G-d is used.  See also <glob>.

<unwind the stack> v. 1. During the execution of a procedural language
   one is said to `unwind the stack' from a called procedure up to a
   caller when one discards the stack frame and any number of frames
   above it, popping back up to the level of the given caller.  In C
   this is done with longjmp/setjmp; in LISP with THROW/CATCH.  This
   is sometimes necessary when handling exceptional conditions.  See
   also <smash the stack>. 2. People can unwind the stack as well, by
   quickly dealing with a bunch of problems "Oh hell, let's do lunch.
   Just a second while I unwind my stack".

<unwind-protect> [MIT, from the name of a LISP operator] n. A task you
   must remember to perform before you leave a place or finish a
   project.  "I have an unwind-protect to call my advisor."

<UNIX> /yoo'niks/ [In the authors' words, "A weak pun on MULTICS"]
   n. A popular interactive time-sharing system originally invented in
   1969 by Ken Thompson after Bell Labs left the MULTICS project,
   mostly so he could play SPACEWAR on a scavenged PDP7. Dennis
   Ritchie, the inventor of C, is considered a co-author of the
   system.  The turning point in UNIX's history came when it was
   reimplemented almost entirely in C in 1974, making it the first
   source-portable operating system.  Fifteen years and a lot of
   changes later UNIX is the most widely used multiuser
   general-purpose operating system in the world.  Many people (q.v.
   <UNIX weenie>) consider this the single most important victory yet
   of hackerdom over industry opposition.  See <Version 7>, <BSD

<UNIX conspiracy> [ITS] n.  According to a conspiracy theory long
   popular among <ITS> and <TOPS-20> fans, UNIX's growth is the result
   of a plot hatched during the 70s at Bell Labs, whose intent was to
   hobble AT&T's competitors by making them dependent upon a system
   whose future evolution was to be under AT&T control.  This would be
   accomplished by disseminating an operating system that is seemingly
   inexpensive and easily portable, but relatively unreliable and
   insecure.  In this view, UNIX was designed to be one of the first
   computer viruses (see <virus>), but a virus spread to computers
   indirectly by people and market forces, rather than directly
   through disks and networks.  Adherents of this "UNIX virus"
   theory like to cite the fact that the well-known quotation "UNIX
   is snake oil" was uttered by DEC president Kenneth Olsen shortly
   before DEC began actively promoting its own family of UNIX

<unixism> n. A piece of code or coding technique that depends on of
   the protected multi-tasking environment with relatively low
   process-spawn overhead that exists on UNIX systems.  Common
   <unixism>s include: gratuitous use of `fork(2)'; the assumption that
   certain undocumented but well-known features of UNIX libraries like
   `stdio(3)' are supported elsewhere; reliance on <obscure>
   side-effects of system calls (use of `sleep(2)' with a zero argument
   to clue the scheduler that you're willing to give up your
   time-slice, for example); the assumption that freshly-allocated
   memory is empty, the assumption that it's safe to never free()
   memory, etc.

<UNIX weenie> [ITS] n. 1. A derogatory pun on "UNIX wizard", common
   among hackers who use UNIX by necessity, but would prefer
   alternatives.  The implication is that, while the person in
   question may consider mastery of UNIX arcana to be a wizardly
   skill, the only real skill involved is the ability to tolerate, and
   the bad taste to wallow in, the incoherence and needless complexity
   that are alleged to infest many UNIX programs.  "This shell script
   tries to parse its arguments in 69 bletcherous ways. It must have
   been written by a real UNIX weenie."  2. A derogatory term for
   anyone who engages in uncritical praise of UNIX.  Often appearing
   in the context "stupid UNIX weenie".  See <Weenix>, <UNIX

<up> adj. 1. Working, in order.  "The down escalator is up."  2.
   <bring up>: v. To create a working version and start it.  "They
   brought up a down system."

<upload> /uhp'lohd/ v. 1. To transfer code or data over a digital comm
   line from a smaller `client' system to a larger `host' one.  Oppose
   <download>.  2. [speculatively] To move the essential patterns and
   algorithms which make up one's mind from one's brain into a
   computer.  Only those who are convinced that such patterns and
   algorithms capture the complete essence of the self view this
   prospect with aplomb.

<urchin> n. See <munchkin>.

<USENET> /yoos'net/ or /yooz'net/ [from "Users' Network"] n. A
   distributed bulletin board system supported mainly by UNIX
   machines, international in scope and probably the largest
   non-profit information utility in existence.  As of early 1990 it
   hosts over 700 topic groups and distributes up to 15 megabytes of
   new technical articles, news, discussion, chatter, and <flamage>
   every day.  See <newsgroup>.

<user> n. 1. Someone doing "real work" with the computer, who uses a
   computer as a means rather than an end.  Someone who pays to use a
   computer.  See <real user>.  2. A programmer who will believe
   anything you tell him.  One who asks silly questions.  (This is
   slightly unfair.  It is true that users ask questions (of
   necessity).  Sometimes they are thoughtful or deep.  Very often
   they are annoying or downright stupid, apparently because the user
   failed to think for two seconds or look in the documentation before
   bothering the maintainer.)  See <luser>.  3. Someone who uses a
   program from the outside, however skillfully, without getting into
   the internals of the program.  One who reports bugs instead of just
   going ahead and fixing them.  Basically, there are two classes of
   people who work with a program: there are implementors (hackers)
   and users (losers).  The users are looked down on by hackers to a
   mild degree because they don't understand the full ramifications of
   the system in all its glory.  (The few users who do are known as
   <real winners>.)  The term is a relative one: a consummate hacker
   may be a user with respect to some program he himself does not
   hack.  A LISP hacker might be one who maintains LISP or one who
   uses LISP (but with the skill of a hacker).  A LISP user is one who
   uses LISP, whether skillfully or not.  Thus there is some overlap
   between the two terms; the subtle distinctions must be resolved by

<user friendly> adj. Programmer-hostile.  Generally used by hackers in
   a critical tone, to describe systems which hold the user's hand so
   obsessively that they make it painful for the more experienced and
   knowledgeable to get any work done.  See <menuitis>, <drool-proof
   paper>, <Macintrash>, <user-obsequious>.

<user-obsequious> adj. Emphatic form of <user friendly>.  Connotes a
   system so verbose, inflexible, and determinedly simple-minded that
   it is nearly unusable. "Design a system any fool can use and only
   a fool will want to use it".

<USG UNIX> /yoo-ess-jee yoo'niks/ n. Refers to AT&T UNIX versions
   after <Version 7>, especially System III and System V releases 1, 2
   and 3.  So called because at that time AT&T's support crew was
   called the `UNIX Support Group'. See <BSD UNIX>.

<UUCPNET> n. The store-and-forward network consisting of all the
   world's UNIX machines (and others running some clone of the UUCP
   (UNIX-to-UNIX Copy Program) software). Any machine reachable via a
   <bang path> is on UUCPNET. See <network address>.

                                {= V =}

<vadding> /vad'ing/ [from VAD, a permutation of ADV (i.e. <ADVENT>),
   used to avoid a particular sysadmin's continual search-and-destroy
   sweeps for the game] n. A leisure-time activity of certain hackers
   involving the covert exploration of the "secret" parts of large
   buildings --- basements, roofs, freight elevators, maintenance
   crawlways, steam tunnels and the like.  A few go so far as to learn
   locksmithing in order to synthesize vadding keys.  The verb is `to
   vad'. The most extreme and dangerous form of vadding is <elevator
   rodeo>, aka <elevator surfing>, a sport played by wrasslin' down a
   thousand-pound elevator car with a three-foot piece of string, and
   then exploiting this mastery in various stimulating ways (such as
   elevator hopping, shaft exploration, rat-racing and the
   ever-popular drop experiments).  Kids, don't try this at home!

<vanilla> adj. Ordinary flavor, standard.  See <flavor>.  When used of
   food, very often does not mean that the food is flavored with
   vanilla extract!  For example, "vanilla-flavored wonton soup" (or
   simply "vanilla wonton soup") means ordinary wonton soup, as
   opposed to hot and sour wonton soup.  Applied to hardware and
   software.  As in "Vanilla Version 7 UNIX can't run on a vanilla
   11/34".  Also used to orthogonalize TTL nomenclature; for instance
   a 74V00 is what TI calls a 7400, as distinct from a 74LS00, etc.
   This word differs from <canonical> in that the latter means "the
   thing you always use (or the way you always do it) unless you have
   some strong reason to do otherwise", whereas <vanilla> simply
   means "ordinary".  For example, when hackers go on a <Great
   Wall>, hot-and-sour wonton soup is the <canonical> wonton soup to
   get (because that is what most of them usually order) even though
   it isn't the <vanilla> wonton soup.

<vannevar> /van'@-var/ n. A bogus technological prediction or
   foredoomed engineering concept, esp. one which fails by implicitly
   assuming that technologies develop linearly, incrementally, and in
   isolation from one another when in fact the learning curve tends to
   be highly nonlinear, revolutions are common, and competition is the
   rule.  The prototype was Vannevar Bush's prediction of "electronic
   brains" the size of the Empire State Building with a
   Niagara-Falls-equivalent cooling system for their tubes and relays,
   at a time when the semiconductor effect had already been
   demonstrated.  Other famous vannevars have included magnetic-bubble
   memory, LISP machines and a paper from the late 1970s that
   purported to prove limits on maximum areal densities for ICs less
   than were in fact exceeded routinely five years later.

<vaporware> n. Products announced far in advance of any shipment
   (which may or may not actually take place).

<var> /veir/ or /vahr/ n. Short for "variable". Compare <arg>,

<VAX> /vaks/ n. 1. [from Virtual Address eXtension] The most
   successful minicomputer design in industry history, possibly
   excepting its immediate ancestor the PDP-11. Between its release in
   1978 and eclipse by <killer micro>s after about 1986 the VAX was
   probably the favorite hacker machine of them all, esp. after the
   1982 release of 4.2BSD UNIX (see <BSD UNIX>). Esp. noted for its
   large, assembler-programmer-friendly instruction set, an asset
   which became a liability after the RISC revolution following about
   1985.  2. A major brand of vacuum cleaner in Britain.  Cited here
   because its alleged sales pitch, "Nothing sucks like a VAX!"
   became a sort of battle-cry of RISC partisans.  Ironically, the
   slogan was actually that of a rival brand called Electrolux.

<VAXen> /vak'sn/ [from "oxen", perhaps influenced by "vixen"] n.
   pl.  The plural standardly used among hackers for the DEC VAX
   computers.  "Our installation has four PDP-10's and twenty
   <vaxen>."  See <boxen>.

<vaxism> n. A piece of code that excebits <vaxocentrism> in critical
   areas.  Compare <PC-ism>, <unixism>.

<vaxocentrism> /vak`soh-sen'trizm/ [analogy with "ethnocentrism"] n.
   A notional disease said to afflict C programmers who persist in
   coding according to certain assumptions valid (esp. under UNIX) on
   <VAXen>, but false elsewhere (this can create substantial
   portability problems). Among these are:

  1.    The assumption that dereferencing a null pointer is safe because
        it is all bits zero, and location 0 is readable and zero (it may
        instead cause an illegal-address trap on non-VAXEN, and even on
        VAXEN under OSs other than BSD UNIX).

  2.    The assumption that pointer and integer types are the same size,
        and that pointers can be stuffed into integer variables and drawn
        back out without being truncated or mangled.

  3.    The assumption that a data type of any size may begin at any
        byte address in memory (for example, that you can freely construct
        and dereference a pointer to a word-sized object at an odd
        address). On many (esp. RISC) architectures better optimized for
        HLL execution speed this is invalid and can cause an illegal
        address fault or bus error.

  4.    The (related) assumption that there is no `padding' at the end
        of types and that in an array you can thus step right from the last
        byte of a previous component to the first byte of the next one.

  5.    The assumption that memory address space is globally flat and
        that the array reference foo[-1] is necessarily valid This is not
        true on segment-addressed machines like Intel chips (yes,
        segmentatation is universally considered a <brain-damaged> way to
        design but that is a separate issue).

  6.    The assumption that objects can be arbitrarily large with no
        special considerations (again, not true on segmented

  7.    The assumption that the parameters of a routine are stored in
        memory, contiguously, and in strictly ascending or descending order
        (fails on many RISC architectures).

  8.    The assumption that bits and addressable units within an object
        are ordered in the same way and that this order is a constant of
        nature (fails on <big-endian> machines).

  9.    The assumption that it is meaningful to compare pointers to
        different objects not located within the same array, or to objects
        of different types (the former fails on segmented architectures,
        the latter on word-oriented machines or others with multiple
        pointer formats).

 10.    The assumption that a pointer to any one type can freely be cast
        into a pointer to any other type (fails on word- oriented machines
        pr others with multiple pointer formats).

 11.    The assumption that "int" is 32 bits (fails on 286-based
        systems under some compilers), or (nearly equivalently) the
        assumption that sizeof(int) == sizeof(long).

 12.    The assumption that argv[] is writeable (fails in some
        embedded-systems C environments).

 13.    The assumption that characters are signed (fails on the 68000
        series and elsewhere).

 14.    The assumption that all pointers are the same size and format,
        which means you don't have to worry about getting the types correct
        in calls (fails on word-oriented machines or others with multiple
        pointer formats).

   Note that a programmer can be validly be accused of vaxocentrism
   even if he/she has never seen a VAX. The terms "vaxocentricity"
   and "all-the-world's-a-VAX syndrome" have been used synonymously.

<veeblefester> /vee'b@l-fes-tr/ [from the "Born Loser" comix via
   Commodore; prob originally from Mad Magazine's "Veeblefeetzer" c.
   1960] n.  Any obnoxious person engaged in the alleged professions
   of marketing or management.  Antonym of <hacker>.  Compare <suit>,

<venus flytrap> [after the plant] n. See <firewall machine>.

<verbiage> /ver'bee-@j/ [IBM] n. Documentation.

<Version 7> alt. V7 /vee-se'vn/ n. The 1978 unsupported release of
   <UNIX> ancestral to all current commercial versions.  Before
   the release of the POSIX/SVID standards V7's features were often
   treated as a UNIX portability baseline.  See <BSD>, <USG UNIX>,
   <UNIX>.  Some old-timers impatient with commercialization and
   kernel bloat still maintain that V7 was the Last True UNIX.

<vi> /vee ie/, *not* /vie/ and *never* /siks/ [from `Visual
   Interface'] n. A screen editor <crufted together> by Bill Joy for
   an early <BSD> version.  Became the de-facto standard UNIX editor
   and a nearly undisputed hacker favorite until the rise of <EMACS>
   after about 1984.  Tends to frustrate new users no end, as it will
   neither take commands while accepting input text nor vice versa,
   and the default setup provides no indication of which mode one is
   in.  Nevertheless it is still widely used (about half the
   respondents in a USENET poll preferred it), and even EMACS fans
   often resort to it as a mail editor and for small editing jobs
   (mainly because it starts up faster than bulky EMACS).  See
   <holy wars>.

<virgin> adj. Unused, in reference to an instantiation of a program.
   "Let's bring up a virgin system and see if it crashes again."
   Esp. useful after contracting a <virus> through <SEX>.  Also, by
   extension, unused buffers and the like within a program.

<virus> [from SF] n. A cracker program that propagates itself by
   `infecting' (embedding itself in) other trusted programs,
   especially operating systems.  See <worm>, <trojan horse>.

<virtual> adj. 1. Common alternative to <logical>, but never used with
   compass directions.  2.  Performing the functions of.  Virtual
   memory acts like real memory but isn't. This word is nearly
   synonymous with <logical>, but is never used of directions.  Note
   that for any thing X, a logical X is either a real X or a virtual
   X, but not both.

<virtual reality> n. 1. Computer simulations that involve 3D graphics
   and use devices such as the Dataglove to allow the user interact
   with the simulation.  See <cyberspace>.  2. A form of network
   interaction incorporating aspects of role-playing games,
   interactive theater, improvisational comedy and "true
   confessions" magazines.  In a "virtual reality" forum (such as
   USENET's alt.callahans newsgroup or the MUD experiments on
   Internet) interaction between the participants is written like a
   shared novel complete with scenery, "foreground characters" which
   may be personae utterly unlike the people who write them, and
   common "background characters" manipulable by all parties.  The
   one iron law is that you may not write irreversible changes to a
   character without the consent of the person who "owns" it.
   Otherwise anything goes.  See <bamf>, <cyberspace>.

<visionary> n. One who hacks vision, in the sense of an Artificial
   Intelligence researcher working on the problem of getting computers
   to "see" things using TV cameras.  (There isn't any problem in
   sending information from a TV camera to a computer.  The problem
   is, how can the computer be programmed to make use of the camera
   information?  See <SMOP>.)

<VMS> /vee em ess/ n. DEC's proprietary operating system for their VAX
   minicomputer; one of the seven or so environments that loom largest
   in hacker folklore.  Many UNIX fans generously concede that VMS
   would probably be the hacker's favorite commercial OS if UNIX
   didn't exist; though true, this makes VMS fans furious.  One major
   hacker gripe with it is its slowness, thus the following limerick:

        There once was a system called VMS
        Of cycles by no means abstemious.
             It's chock-full of hacks
             And runs on a VAX
        And makes my poor stomach all squeamious.
     			---The Great Quux

   See also <VAX>, <TOPS-10>, <TOPS-20>, <UNIX>.

<voodoo programming> [from George Bush's "voodoo economics"] n. Use
   by guess or cookbook of an <obscure>, <hairy> system feature or
   algorithm which one does not truly understand.  The implication is
   that the technique may not work, and if it doesn't one will never
   know why.  Compare <magic>, <deep magic>, <heavy wizardry>.

<vulcan nerve pinch> n. [From the old Star Trek TV series via
   Commodore Amiga hackers] The keyboard combination that forces a
   soft-boot or jump to ROM monitor (on machines that support such a
   feature). On many micros this is Ctrl-Alt-Del; on Macintoshes, it
   is <Cmd>-<Power switch>!  Also called <three-finger salute>.

<vulture capitalist> n. Pejorative hackerism for "venture
   capitalist", deriving from the common practice of pushing
   contracts that deprive inventors of both control over their own
   innovations and most of the money they ought to have made from

                                {= W =}

<wabbit> /wab'it/ [almost certainly from Elmer Fudd's immortal line
   "you wascal wabbit!"] n. 1. A legendary early hack reported on a
   System/360 at RPI and elsewhere around 1978. The program would
   reproduce itself twice every time it was run, eventually crashing
   the system.  2. By extension, any hack that includes infinite
   self-replication but is not a <virus> or <worm>.  See also <cookie

<waldo> /wol'doh/ [probably taken from the story "Waldo", by
   Heinlein, which is where the term was first used to mean a remote
   mechanical agent controlled by a human limb] At Harvard
   (particularly by Tom Cheatham and students) this is used instead of
   <foobar> as a meta-syntactic variable and general nonsense word.
   See <foo>, <bar>, <foobar>, <quux>.

<walk> n.,vt. Traversal of an actual or <logical> data structure,
   especially a linked-list data structure in <core>.  See also
   <codewalker>, <silly-walk>, <clobber>.

<walking drives> n. An occasional failure mode of magnetic-disk drives
   back in the days when they were 14" wide <washing machine>s. Those
   old <dinosaur> parts carried terrific angular momentum; the
   combination of a misaligned spindle or worn bearings and stick-slip
   interactions with the floor could cause them to "walk" across a
   room, lurching alternate corners forward a couple of millimeters at
   a time.  There is a legend about a drive that walked over to the
   only door to the computer room and jammed it shut; the staff had to
   cut a hole in the wall in order to get at it! Walking could also be
   induced by certain patterns of drive access (a fast seek across the
   whole width of the disk, followed by a slow seek in the other
   direction).  It is known that some bands of old-time hackers
   figured out how to induce disk-accessing patterns that would do
   this to particular drive models and held disk-drive races.  This is
   not a joke!

<wall> [WPI] interj. 1. An indication of confusion, usually spoken
   with a quizzical tone.  "Wall??"  2. A request for further
   explication.  Compare <octal forty>.

   It is said that "WALL?"  really came from "talking to a blank
   wall".  It was initially used in situations where, after one
   carefully answered a question, the questioner stared at you
   blankly, having understood nothing that was explained.  One would
   then throw out a "HELLO, WALL?" to elicit some sort of response
   from the questioner.  Later, confused questioners began voicing
   "WALL?" themselves.

   There is an anecdote about a child in a hospital who is addressed
   by a nurse over an intercom and replies "What do you want, Wall?"

<wall time> n. 1. `Real world' time (what the clock on the wall shows)
   as opposed to the system clock's idea of time. 2. The real running
   time of a program, as opposed to the number of <clocks> required to
   execute it (on a timesharing system these will differ, as no one
   program gets all the <clocks>).

<wallpaper> n. 1. A file containing a listing (e.g., assembly listing)
   or transcript, esp. a file containing a transcript of all or part
   of a login session.  (The idea was that the LPT paper for such
   listings was essentially good only for wallpaper, as evidenced at
   Stanford where it was used as such to cover windows.)  Usage: not
   often used now, esp. since other systems have developed other terms
   for it (e.g., PHOTO on TWENEX). However, the UNIX world doesn't
   have an equivalent term, so perhaps <wallpaper> will take hold
   there.  The term probably originated on ITS, where the commands to
   begin and end transcript files were :WALBEG and :WALEND, with
   default file DSK:WALL PAPER.  2. The background pattern used on
   graphical workstations (this is jargon under the "Windows"
   graphical user interface to MS-DOS).  3. <wallpaper file> n. The
   file that contains the wallpaper information before it is actually
   printed on paper.  (Sometimes you don't intend ever to produce a
   real paper copy of the file, because you can look at the file
   directly on your terminal, but it is still called a "wallpaper

<washing machine> n. Old-style hard disks in floor-standing cabinets.
   So called because of the size of the cabinet and the
   "top-loading" access to the media packs -- and, of course, they
   were always set on "spin cycle".  The washing-machine idiom
   transcends language barriers; it's even used in Russian hacker
   jargon.  See <walking drives>.  The thick channel cables connecting
   these were called "bit hoses" (see HOSE).

<weasel> [Cambridge University] A "naive user", one who deliberately
   or accidentally does things which are stupid or ill-advised.
   Roughly synonymous with <luser>.

<wedged> adj. 1. To be stuck, incapable of proceeding without help.
   This is different from having crashed.  If the system has crashed,
   then it has become totally non-functioning.  If the system is
   wedged, it is trying to do something but cannot make progress; it
   may be capable of doing a few things, but not be fully operational.
   For example, the system may become wedged if the disk controller
   fries; there are some things you can do without using the disks,
   but not many.  Being wedged is slightly milder than being <hung>.
   Also see <gronk>, <locked up>, <hosed>.  2. This term is sometimes
   used to describe a <deadlock> condition.  3.  Often refers to
   humans suffering misconceptions.  4. [UNIX] Specifically used to
   describe the state of a TTY left in a losing state by abort of a
   screen-oriented program or one that has messed with the line
   discipline in some obscure way. 5. <wedgitude> (wedj'i-tood) n.
   The quality or state of being wedged.

<weeble> /weeb'l/ [Cambridge University] interj. Use to denote
   frustration, usually at amazing stupidity.  "I stuck the disk in
   upside down." "Weeble..."  Compare <gurfle>.

<weeds> n. Refers to development projects or algorithms that have no
   possible relevance or practical application.  Comes from "off in
   the weeds".  Used in phrases like "lexical analysis for microcode
   is serious weeds..."

<Weenix> [ITS] n. A derogatory term for <UNIX>, derived from <UNIX

<well-behaved> adj. 1. [primarily <MS-DOS>] Said of software
   conforming to system interface guidelines and standards.  Well
   behaved software uses the operating system to do chores such as
   keyboard input, allocating memory and drawing graphics.  Oppose
   <ill-behaved>.  2.  Software that does its job quietly and without
   counterintuitive effects.  Esp. said of software having an
   interface spec sufficiently simple and well-defined that it can be
   used as a tool by other software.

<well-connected> adj. Said of a computer installation, this means it
   has reliable email links with the network and/or relays a large
   fraction of available <USENET> newsgroups.

<wetware> [prob. from the novels of Rudy Rucker] n. 1. The human
   brain, as opposed to computer hardware or software (as in "Wetware
   has at most 7 +/- 2 registers").  2.  Human beings (programmers,
   operators, administrators) attached to a computer system, as
   opposed to the system's hardware or software.

<what> n. The question mark character (`?').  See <ques>.  Usage:
   rare, used particularly in conjunction with <wow>.

<wheel> [from Twenex, q.v.] n. A privileged user or <wizard> (sense
   #2).  The term was invented on the TENEX operating system, and
   carried over to <TWENEX>, Xerox-IFS, and others.  It entered the
   UNIX culture from <TWENEX> and has been gaining popularity there
   (esp.  at university sites).  Privilege bits are sometimes called
   "wheel bits".  The state of being in a privileged logon is
   sometimes called "wheel mode". See also <root>.

<wheel wars> [Stanford University] A period in <larval stage> during
   which student wheels hack each other by attempting to log each
   other out of the system, delete each other's files, and otherwise
   wreak havoc, usually at the expense of the lesser users.

<White Book> n. Syn. <K&R>.

<whizzy> (sometimes `wizzy') [Sun] adj. A <cuspy> program; usually
   feature-rich and well presented.

<WIBNI> Bell Labs, Wouldn't It Be Nice If] n. What most requirements
   documents/specifications consist entirely of.  Compare <IWBNI>.

<widget> n.  1. A meta-thing.  Used to stand for a real object in
   didactic examples (especially database tutorials).  Legend has it
   that the original widgets were holders for buggy whips.  2. [poss.
   from "window gadget"] A user interface object in X Window System
   graphical user interfaces.

<wiggles> n. [scientific computation] In solving partial differential
   equations by finite difference and similar methods, wiggles are
   sawtooth (up-down-up-down) oscillations at the shortest wavelength
   representable on the grid.  If an algorithm is unstable, this is
   often the most unstable waveform, so it grows to dominate the
   solution.  Alternatively, stable (though inaccurate) wiggles can be
   generated near a discontinuity by a Gibbs phenomenon.

<WIMP environment> n. [acronymic from Window, Icon, Mouse, Pointer] A
   graphical-user-interface based environment, as described by a
   hacker who prefers command-line interfaces for their superior
   flexibility and extensibility.

<win> [from MIT jargon] 1. v. To succeed.  A program wins if no
   unexpected conditions arise.  2.  Success, or a specific instance
   thereof.  A pleasing outcome.  A <feature>.  3. <big win>: n.
   Serendipity.  Emphatic forms: "moby win", "super win",
   "hyper-win" (often used interjectively as a reply).  For some
   reason "suitable win" is also common at MIT, usually in reference
   to a satisfactory solution to a problem.  4. <win big> v. To
   experience serendipity.  "I went shopping and won big; there was a
   two-for-one sale." 5.  <win win> interj. Expresses pleasure at a
   <win>.  Oppose <lose>.

<winnage> /win'@j/ n. The situation when a lossage is corrected, or
   when something is winning.  Quite rare.  Usage: also quite rare.

<winner> 1. n. An unexpectedly good situation, program, programmer or
   person.  2. <real winner>: Often sarcastic, but also used as high

<winnitude> /win'i-tood/ n. The quality of winning (as opposed to
   <winnage>, which is the result of winning).  "That's really great!
   Boy, what winnitude!"

<wirehead> n. [prob. from notional SF slang for an electrical brain
   stimulation junkie] 1. A hardware hacker, especially one who
   concentrates on communications hardware.  2. An expert in local
   area networks.  A wirehead can be a network software wizard too,
   but will always have the ability to deal with network hardware,
   down to the smallest component.  Wireheads are known for their
   ability to lash up an Ethernet terminator from spare resistors, for

<wish list> n. A list of desired features or bug fixes that probably
   won't get done for a long time, usually because the person
   responsible for the code is too busy or can't think of a clean way
   to do it.

<wizard> n.  1. A person who knows how a complex piece of software or
   hardware works (that is, who <grok>s it); esp.  someone who can
   find and fix bugs quickly in an emergency.  This term differs
   somewhat from <hacker>.  Someone is a hacker if he has general
   hacking ability, but is only a wizard with respect to something if
   he has specific detailed knowledge of that thing.  A good hacker
   could become a wizard for something given the time to study it.  2.
   A person who is permitted to do things forbidden to ordinary
   people.  For example, an Adventure wizard at Stanford may play the
   Adventure game during the day, which is forbidden (the program
   simply refuses to play) to most people because it uselessly
   consumes too many <cycle>s. 3. A UNIX expert, esp. a UNIX systems
   programmer.  This usage is well enough established that "UNIX
   Wizard" is a recognized job title at some corporations and to most
   headhunters.  See <guru>.

<wizard book> n. Abelson and Sussman's "Structure and Interpretation
   of Computer Programs", an excellent CS text used in introductory
   courses at MIT.  So called because of the wizard on the cover of
   the MIT Press edition.

<wizard mode> [from nethack] n. A special access mode of a program or
   system, usually passworded, that permits some users godlike
   privileges.  Generally not used for operating systems themselves
   (<root mode> or <wheel mode> would be used instead).

<wizardly> adj. Pertaining to wizards.  A wizardly <feature> is one
   that only a wizard could understand or use properly.

<WOMBAT> [Waste Of Money, Brains and Time] adj. Applied to problems
   which are both profoundly <uninteresting> in themselves and
   unlikely to benefit anyone interesting even if solved.  Often used
   in fanciful constructions such as "wrestling with a wombat". See
   also <crawling horror>, <SMOP>.  Also note the rather different
   usage as a meta-syntactic variable under <COMMONWEALTH HACKISH>

<wonky> /won'kee/ [from Australian slang] adj. Yet another approximate
   synonym for <broken>.  Specifically connotes a malfunction which
   produces behavior seen as crazy, humorous, or amusingly perverse.
   "That was the day the printer's font logic went wonky and
   everybody's listings came out in Elvish."  Also in "wonked out".
   See <funky>, <demented>.

<worm> [from `tapeworm' in John Brunner's "Shockwave Rider", via
   XEROX PARC] n. A cracker program that propagates itself over a
   network, reproducing itself as it goes.  See <virus>.  Perhaps the
   best known example was RTM's `Internet Worm' in '88, a `benign' one
   that got out of control and shut down hundreds of Suns and VAXen
   nationwide.  See also <cracker>, <trojan horse>, <ice>.

<wound around the axle> adj. In an infinite loop.  Often used by older
   computer types.

<wow> See <excl>.

<wrap around> v. (also n. `wraparound' and v. shorthand "wrap") 1.
   This is "jargon" in its normal computer usage, i.e., describing
   the action of a counter that starts over at 0 or at <minus
   infinity> after its maximum value has been reached, and continues
   incrementing, either because it is programmed to do so, or because
   of an overflow like a car's odometer starting over at 0.  2. To
   <change phase> gradually and continuously by maintaining a steady
   wake-sleep cycle somewhat longer than 24 hours, e.g. living 6 long
   days in a week.

<write-only code> [a play on "read-only memory"] n. Code
   sufficiently arcane, complex, or ill-structured that it cannot be
   modified or even comprehended by anyone but the original author.  A
   <Bad Thing>.

<write-only language> n. A language with syntax (or semantics)
   sufficiently dense and bizarre that any routine of significant size
   is <write-only code>. A sobriquet often applied to APL,
   though INTERCAL certainly deserves it more.

<write-only memory> n. The obvoius antonym to "read-only memory".
   In frustration with the long and seemingly useless chain of
   approvals required of component specifications, during which no
   actual checking seemed to occur, an engineer at Signetics created a
   specification for a write-only memory, and included it with a bunch
   of other specifications to be approved.  This inclusion only came
   to the attention of Signetics when regular customers started
   calling and asking for pricing information.  Signetics published a
   corrected edition of the data book, and requested the return of the
   "erroneous" ones.  Later, about 1974, Signetics bought a double
   page spread in Electronics magazine's April issue, and used the
   spec as an April Fools' day joke.  Instead of the more conventional
   characteristic curves, the 25120 "fully encoded, 9046 x N, Random
   Access, write-only-memory" data sheet included diagrams of "bit
   capacity vs. Temp.", "Iff vs. Vff", "Number of pins remaining
   vs. number of socket insertions" and "AQL vs.  selling price".
   The 25120 required a 6.3 VAC VFF supply, a +10V VCC, and VDD of 0V,
   +/- 2%.

<Wrong Thing, the> n. A design, action or decision which is clearly
   incorrect or inappropriate.  Often capitalized; always emphasized
   in speech as if capitalized.  The opposite of the Right Thing; more
   generally, anything that is not the Right Thing.  In cases were
   "the good is the enemy of the best", the merely good, while good,
   is nevertheless the Wrong Thing.

<wugga wugga> /wuh'guh wuh'guh/ n. Imaginary sound that a computer
   program makes as it labors with a tedious or difficult task.
   Compare <cruncha cruncha cruncha>, <grind> (sense #4).

<WYSIWYG> /wiz'ee-wig/ adj. User interface (usu. text or graphics
   editor) characterized as being "what you see is what you get;" as
   opposed to one which uses more-or-less obscure commands which do
   not result in immediate visual feedback.  The term can be mildly
   derogatory, as it is often used to refer to dumbed-down interfaces
   targeted at non-programmers, while a hacker has no fear of obscure
   commands.  On the other hand, EMACS was one of the very first
   WYSIWYG editors, replacing (actually, at first overlaying) the
   extremely obscure, command-based TECO.

                                {= X =}

<x> /eks/ n. 1. Used in various speech and writing contexts in roughly
   its algebraic sense of "unknown within a set defined by context"
   (compare `N').  Thus: the abbreviation 680x0 stands for 68000,
   68010, 68020, 68030 or 68040, and 80x86 stands for 80186, 80286
   80386 or 80486 (note that a UNIX hacker might write these as
   680[01234]0 and 80[1234]86 or 680?0 and 80?86 respectively; see
   GLOB).  2. An over-sized, over-featured, over-engineered window
   system developed at MIT and widely used on UNIX systems.

<xor> /eks'ohr/ conj.  Exclusive or.  "A xor B" means "A or B, but
   not both".  Example: "I want to get cherry pie xor a banana
   split."  This derives from the technical use of the term as a
   function on truth-values that is true if either of two arguments is
   true but not both.

<xref> /eks'ref/ v.,n. Hackish standard abbreviation for

<XXX> /eks-eks-eks/ n. A marker that attention is needed.  Commonly
   used in program comments to indicate areas that are <kluged up> or
   need to be.  Some hackers liken XXX code to pornographic movies
   that contain the symbol.

<xyzzy> /eks-wie-zee-zee-wie/, /ik-zi'zee/, /eks-wie-ziz'ee/ [from the
   ADVENT game] adj.  The <canonical> "magic word".  This comes from
   <ADVENT>, in which the idea is to explore an underground cave with
   many rooms to collect treasure.  If you type XYZZY at the
   appropriate time, you can move instantly between two otherwise
   distant points.  If, therefore, you encounter some bit of MAGIC,
   you might remark on this quite succinctly by saying simply
   "XYZZY"!  Example: "Ordinarily you can't look at someone else's
   screen if he has protected it, but if you type
   quadruple-bucky-clear the system will let you do it anyway."
   "XYZZY!"  XYZZY has actually been implemented as an undocumented
   no-op command on several OSs; in Data General's AOS/VS, for
   example, it would typically respond "Nothing happens." just as
   <ADVENT> did if the magic was invoked at the wrong spot or before a
   player had performed the action that enabled the word.  See

                                {= Y =}

<YA*> ["Yet Another"] abbrev.  In hackish acronyms this almost
   invariably expands to <Yet Another> following the precedent set by
   UNIX `yacc(1)'. See <YABA>.

<YABA> /ya'buh/ [Cambridge University] n. Yet Another Bloody Acronym.
   Whenever some program is being named, someone invariably suggests
   that it be given a name which is acronymic.  The response from
   those with a trace of originality is to remark ironically that the
   proposed name would then be "YABA-compatible". Also used in
   response to questions like "What is WYSIWYG?" "YABA."  See also

<YAUN> /yawn/ [Acronym for "Yet Another UNIX Nerd"] n. Reported from
   the San Diego Computer Society (predominently a microcomputer
   users' group) as a good-natured punning insult aimed at UNIX

<Yet Another> adj. [UNIX] From UNIX's `yacc(1)' ("Yet Another Compiler-
   Compiler") LALR parser generator.  1. Of your own work: humorous
   allusion often used in titles to acknowledge that the topic is not
   original -- though the content is.  As in "Yet Another AI Group"
   or "Yet Another Simulated Annealing Algorithm".  2. Of other's
   work: describes something of which there are far too many.  See
   also <YA*>, <YABA>, <YAUN>.

<You are not expected to understand this.> cav. [UNIX] Canonical
   comment describing something <magic> or too complicated to bother
   explaining properly.  From a comment in the context-switching code
   of the V6 UNIX kernel.

<You know you've been hacking too long when...> The set-up line
   for a genre of one-liners told by hackers about themselves.  These
   include the following:

   * not only do you check your email more often than your paper
     mail, but you remember your <network address> faster than your
     postal one.
   * your <SO> kisses you on the neck and the first thing you
     think is "Uh, oh, <priority interrupt>".
   * you go to balance your checkbook and discover that you're
     doing it in octal.
   * your computers have a higher street value than your car.
   * `round numbers' are powers of 2, not 10.
   * you've woken up more than once to recall of a dream in
     some programming language.
   * you realize you've never met half of your best friends.

   All but one of these have been reliably reported as hacker traits
   (some of them quite often). Even hackers may have trouble spotting
   the ringer.

<Your mileage may vary.> cav. [from the standard disclaimer attached
   to EPA mileage ratings by American car manufacturers] A ritual
   warning often found in UNIX freeware distributions.  Translates
   roughly as "Hey, I tried to write this portably but who
   *knows* what'll happen on your system?"

<Yow!> /yow/ [from Zippy the Pinhead comix] interj. Favored hacker
   expression of humorous surprise or emphasis. "Yow! Check out what
   happens when you twiddle the foo option on this display hack!"
   Compare <gurfle>.

<yoyo mode> n. State in which the system is said to be when it rapidly
   alternates several times between being up and being down.

<Yu-Shiang whole fish> /yoo-shyang hohl fish/ n. obs.  The character
   gamma (extended SAIL ASCII 11), which with a loop in its tail looks
   like a little fish swimming down the page.  The term is actually
   the name of a Chinese dish in which a fish is cooked whole (not
   <parse>d) and covered with Yu Shiang sauce.  Usage: was used
   primarily by people on the MIT LISP Machine, which could display
   this character on the screen.  Tends to elicit incredulity from
   people who hear about it second-hand.

                                {= Z =}

<zap> 1. n. Spiciness.  2. v. To make food spicy.  3. v. To make
   someone "suffer" by making his food spicy.  (Most hackers love
   spicy food.  Hot-and-sour soup is considered wimpy unless it makes
   you blow your nose for the rest of the meal.)  4. ZAPPED adj.
   Spicy.  This term is used to distinguish between food that is hot
   (in temperature) and food that is "hot", that is, spicy.  For
   example, the Chinese appetizer Bon Bon Chicken is a kind of chicken
   salad that is cold but zapped.  See also <ORIENTAL FOOD>, <laser
   chicken>.  5. To modify, usually to correct.  Also implies surgical
   precision. (In some communities, used to describe modifying a
   program's binary executable.)  6. To erase or reset.

<zen> v. To figure out something by meditation, or by a sudden flash
   of enlightenment.  Originally applied to bugs, but occasionally
   applied to problems of life in general. "How'd you figure out the
   buffer allocation problem?" "Oh, I zenned it".  Contrast <grok>,
   which connotes a time-extended version of zenning a system.
   Compare <hack mode>.

<zero> v. 1. To set to zero.  Usually said of small pieces of data,
   such as bits or words.  2. To erase; to discard all data from.
   Said of disks and directories, where "zeroing" need not involve
   actually writing zeroes throughout the area being zeroed.  One may
   speak of something being "logically zeroed" rather than being
   "physically zeroed".  See <scribble>.

<zeroth> /zee'rohth/ adj. [C] First.  Comes from C's 0-based indexing
   of arrays.

<zipperhead> [IBM] n. A person with a closed mind.

<zombie> [UNIX] n. A process which has died but has not yet
   relinquished its process table slot (because the parent process
   hasn't executed a `wait(2)' for it yet).  These show up in `ps(1)'
   listings occasionally.  Compare <orphan>.

<zork> /zork/ n. Second of the great early experiments in computer
   fantasy gaming; see <ADVENT>. Originally written on MIT-DMS during
   the late seventies, later distributed with BSD UNIX and
   commercialized as "The Zork Trilogy" by Infocom.

Appendix A: Hacker Folklore

This appendix contains several fables and legends which illuminate
the meaning of various entries in the main text.  All of this material
except THE UNTIMELY DEMISE OF MABEL THE MONKEY appeared in the 1983
paper edition of the Jargon File (but not in the previous on-line

The Meaning of "Hack"

"The word HACK doesn't really have 69 different meanings", according
to Phil Agre, an MIT hacker.  "In fact, HACK has only one meaning, an
extremely subtle and profound one which defies articulation.  Which
connotation is implied by a given use of the word depends in similarly
profound ways on the context.  Similar remarks apply to a couple of
other hacker words, most notably RANDOM."

Hacking might be characterized as "an appropriate application of
ingenuity".  Whether the result is a quick-and-dirty patchwork job or
a carefully crafted work of art, you have to admire the cleverness
that went into it.

An important secondary meaning of `hack' is `a creative practical
joke'. This kind of hack is often easier to explain to non-hackers
than the programming kind.  Accordingly, here are three examples of
practical joke hacks:

In 1961, students from Caltech (California Institute of Technology in
Pasadena) hacked the Rose Bowl football game.  One student posed as a
reporter and "interviewed" the director of the University of
Washington card stunts (such stunts involve people in the stands who
hold up colored cards to make pictures).  The reporter learned exactly
how the stunts were operated, and also that the director would be out
to dinner later.

While the director was eating, the students (who called themselves the
"Fiendish Fourteen") picked a lock and stole one of the direction
sheets for the card stunts.  They then had a printer run off 2300
copies of the sheet.  The next day they picked the lock again and
stole the master plans for the stunts, large sheets of graph paper
colored in with the stunt pictures.  Using these as a guide, they
carefully made "corrections" for three of the stunts on the
duplicate instruction sheets.  Finally, they broke in once more,
replacing the stolen master plans and substituting the stack of
altered instruction sheets for the original set.

The result was that three of the pictures were totally different.
Instead of spelling "WASHINGTON", the word "CALTECH" was flashed.
Another stunt showed the word "HUSKIES", the Washington nickname,
but spelled it backwards.  And what was supposed to have been a
picture of a husky instead showed a beaver.  (Both Caltech and MIT use
the beaver as a mascot.  Beavers are nature's engineers.)

After the game, the Washington faculty athletic representative said,
"Some thought it ingenious; others were indignant."  The Washington
student body president remarked, "No hard feelings, but at the time
it was unbelievable.  We were amazed."

This is now considered a classic hack, particularly because revising
the direction sheets constituted a form of programming not unlike
computer programming.

Another classic hack:

One winter, late at night, an MIT fraternity hosed down an underpass
that is part of a commuter expressway near MIT.  This produced an ice
slick that "trapped" a couple of small cars: they didn't have the
momentum or traction to climb out of the underpass.  While it was
clever to apply some simple science to trap a car, it was also very
dangerous as it could have caused a collision.  Therefore this was a
very poor hack overall.  (There is another story about an even less
appealing hack in which some MIT students used thermite to weld a
trolley car to its tracks.  The story may be apocryphal, however.)

And yet another:

On November 20, 1982, MIT hacked the Harvard-Yale football game.  Just
after Harvard's second touchdown against Yale in the second quarter, a
small black ball popped up out of the ground at the 40-yard line, and
grew bigger, and bigger, and bigger.  The letters "MIT" appeared all
over the ball.  As the players and officials stood around gawking, the
ball grew to six feet in diameter and then burst with a bang and a
cloud of white smoke.

As the Boston Globe later reported, "If you want to know the truth,
M.I.T. won The Game."

The prank had taken weeks of careful planning by members of MIT's
Delta Kappa Epsilon fraternity.  The device consisted of a weather
balloon, a hydraulic ram powered by Freon gas to lift it out of the
ground, and a vacuum-cleaner motor to inflate it.  They made eight
separate expeditions to Harvard Stadium between 1 and 5 AM, in which
they located an unused 110-volt circuit in the stadium, and ran buried
wiring from the stadium circuit to the 40-yard line, where they buried
the balloon device.  When the time came to activate the device, two
fraternity members had merely to flip a circuit breaker and push a
plug into an outlet.

This stunt had all the earmarks of a perfect hack: surprise,
publicity, the ingenious use of technology, safety, and harmlessness.
The use of manual control allowed the prank to be timed so as not to
disrupt the game (it was set off between plays, so the outcome of the
game would not be unduly affected).  The perpetrators had even
thoughtfully attached a note to the balloon explaining that the device
was not dangerous and contained no explosives.

Harvard president Derek Bok commented: "They have an awful lot of
clever people down there at MIT, and they did it again."  President
Paul E. Gray of MIT said, "There is absolutely no truth to the rumor
that I had anything to do with it, but I wish there were."  Such is
the way of all good hacks.

The Untimely Demise of Mabel the Monkey (a Cautionary Tale)

   The following, modulo a couple of inserted commas and capitalization
changes for readability, is the exact text of a famous USENET message.
The reader may wish to review the definitions of PM and MOUNT in the main
text before continuing.

     Date: Wed 3 Sep 86 16:46:31-EDT
     From: "Art Evans" <Evans@TL-20B.ARPA>
     Subject: Always Mount a Scratch Monkey
     To: Risks@CSL.SRI.COM

My friend Bud used to be the intercept man at a computer vendor for
calls when an irate customer called.  Seems one day Bud was sitting at
his desk when the phone rang.
     Bud:       Hello.                 Voice:      YOU KILLED MABEL!!
     B:         Excuse me?             V:          YOU KILLED MABEL!!

This went on for a couple of minutes and Bud was getting nowhere, so he
decided to alter his approach to the customer.

Well, to avoid making a long story even longer, I will abbreviate what had
happened.  The customer was a Biologist at the University of Blah-de-blah,
and he had one of our computers that controlled gas mixtures that Mabel (the
monkey) breathed.  Now, Mabel was not your ordinary monkey.  The University
had spent years teaching Mabel to swim, and they were studying the effects
that different gas mixtures had on her physiology.  It turns out that the
repair folks had just gotten a new Calibrated Power Supply (used to
calibrate analog equipment), and at their first opportunity decided to
calibrate the D/A converters in that computer.  This changed some of the gas
mixtures and poor Mabel was asphyxiated.  Well, Bud then called the branch
manager for the repair folks:

     Manager:     Hello
     B:           This is Bud, I heard you did a PM at the University of
     M:           Yes, we really performed a complete PM.  What can I do
                  for you?
     B:           Can you swim?

The moral is, of course, that you should always mount a scratch monkey.


There are several morals here related to risks in use of computers.
Examples include, "If it ain't broken, don't fix it."  However, the
cautious philosophical approach implied by "always mount a scratch
monkey" says a lot that we should keep in mind.

     Art Evans
     Tartan Labs

TV Typewriters: A Tale Of Hackish Ingenuity

Here is a true story about a glass tty.  One day an MIT hacker was in
a motorcycle accident and broke his leg.  He had to stay in the
hospital quite a while, and got restless because he couldn't HACK (use
the computer).  Two of his friends therefore took a display terminal
and a telephone connection for it to the hospital, so that he could
use the computer by telephone from his hospital bed.

Now this happened some years before the spread of home computers, and
computer terminals were not a familiar sight to the average person.
When the two friends got to the hospital, a guard stopped them and
asked what they were carrying.  They explained that they wanted to
take a computer terminal to their friend who was a patient.

The guard got out his list of things that patients were permitted to
have in their rooms: TV, radio, electric razor, typewriter, tape
player...  no computer terminals.  Computer terminals weren't on the
list, so they couldn't take it in.  Rules are rules.

Fair enough, said the two friends, and they left again.  They were
frustrated, of course, because they knew that the terminal was as
harmless as a TV or anything else on the list... which gave them an

The next day they returned, and the same thing happened: a guard
stopped them and asked what they were carrying.  They said, "This is
a TV typewriter!"  The guard was skeptical, so they plugged it in and
demonstrated it.  "See?  You just type on the keyboard and what you
type shows up on the TV screen."  Now the guard didn't stop to think
about how utterly useless a typewriter would be that didn't produce
any paper copies of what you typed; but this was clearly a TV
typewriter, no doubt about it.  So he checked his list: "A TV is all
right, a typewriter is all right... okay, take it on in!"

Two Stories About "Magic" (As Told By Guy Steele)

When Barbara Steele was in her fifth month of pregnancy, her doctor
sent her to a specialist to have a sonogram made to determine whether
there were twins.  She dragged her husband Guy along to the
appointment.  It was quite fascinating; as the doctor moved an
instrument along the skin, a small TV screen showed cross-sectional
pictures of the abdomen.

Now Barbara and I had both studied computer science at MIT, and we
both saw that some complex computerized image-processing was involved.
Out of curiosity, we asked the doctor how it was done, hoping to learn
some details about the mathematics involved.  The doctor, not knowing
our educational background, simply said, "The probe sends out sound
waves, which bounce off the internal organs.  A microphone picks up
the echoes, like radar, and send the signals to a computer---and the
computer makes a picture."  Thanks a lot!  Now a hacker would have
said, "... and the computer *magically* makes a picture",
implicitly acknowledging that he has glossed over an extremely
complicated process.

Some years ago I was snooping around in the cabinets that housed the
MIT AI Lab's PDP-10, and noticed a little switch glued to the frame of
one cabinet.  It was obviously a homebrew job, added by one of the
lab's hardware hackers (no one know who).

You don't touch an unknown switch on a computer without knowing what
it does, because you might crash the computer.  The switch was labeled
in a most unhelpful way.  It had two positions, and scrawled in pencil
on the metal switch body were the words "magic" and "more magic".
The switch was in the "more magic" position.

I called another hacker over to look at it.  He had never seen the
switch before either.  Closer examination revealed that the switch
only had one wire running to it!  The other end of the wire did
disappear into the maze of wires inside the computer, but it's a basic
fact of electricity that a switch can't do anything unless there are
two wires connected to it.  This switch had a wire connected on one
side and no wire on its other side.

It was clear that this switch was someone's idea of a silly joke.
Convinced by our reasoning that the switch was inoperative, we flipped
it.  The computer instantly crashed.

Imagine our utter astonishment.  We wrote it off as coincidence, but
nevertheless restored the switch to the "more magic" position before
reviving the computer.

A year later, I told this story to yet another hacker, David Moon as I
recall.  He clearly doubted my sanity, or suspected me of a
supernatural belief in the power of this switch, or perhaps thought I
was fooling him with a bogus saga.  To prove it to him, I showed him
the very switch, still glued to the cabinet frame with only one wire
connected to it, still in the "more magic" position.  We scrutinized
the switch and its lone connection, and found that the other end of
the wire, though connected to the computer wiring, was connected to a
ground pin.  That clearly made the switch doubly useless: not only was
it electrically nonoperative, but it was connected to a place that
couldn't affect anything anyway.  So we flipped the switch.

The computer promptly crashed.

This time we ran for Richard Greenblatt, a long-time MIT hacker, who
was close at hand.  He had never noticed the switch before, either.
He inspected it, concluded it was useless, got some diagonal cutters
and diked it out.  We then revived the computer and it ran fine ever

We still don't know how the switch crashed the machine.  There is a
theory that some circuit near the ground pin was marginal, and
flipping the switch changed the electrical capacitance enough to upset
the circuit as millionth-of-a-second pulses went through it.  But
we'll never know for sure; all we can really say is that the switch
was MAGIC.

I still have that switch in my basement.  Maybe I'm silly, but I
usually keep it set on "more magic."

A Selection of AI Koans

   These are perhaps the funniest examples of a genre of jokes told at
the MIT AI lab about various noted computer scientists and hackers.

* * *

   A novice was trying to fix a broken Lisp machine by turning the power
off and on.

   Knight, seeing what the student was doing spoke sternly: "You can not
fix a machine by just power-cycling it with no understanding of what
is going wrong."

   Knight turned the machine off and on.

   The machine worked.

[Ed note: This is much funnier if you know that Tom Knight was one of the
   Lisp machine's principal designers]

* * *

One day a student came to Moon and said, "I understand how to
make a better garbage collector.  We must keep a reference count
of the pointers to each cons."

Moon patiently told the student the following story:

      "One day a student came to Moon and said, "I understand how
      to make a better garbage collector...

[Ed. note: The point here is technical.  Pure reference-count garbage
   collectors have problems with `pathological' structures that point
   to themselves.]

* * *

In the days when Sussman was a novice Minsky once came to him as
he sat hacking at the PDP-6.

   "What are you doing?", asked Minsky.

   "I am training a randomly wired neural net to play Tic-Tac-Toe",
Sussman replied.

   "Why is the net wired randomly?", asked Minsky.

   "I do not want it to have any preconceptions of how to play",
Sussman said.

   Minsky then shut his eyes.

   "Why do you close your eyes?", Sussman asked his teacher.

   "So that the room will be empty."

   At that moment, Sussman was enlightened.

* * *

   A disciple of another sect once came to Drescher as he was
eating his morning meal.

   "I would like to give you this personality test", said the
outsider, "because I want you to be happy."

   Drescher took the paper that was offered him and put it
into the toaster, saying:

   "I wish the toaster to be happy, too."


This story says a lot about the style of the ITS culture. 

On the ITS system there was a program that allowed you to see what is
being printed on someone else's terminal.  It worked by "spying" on
the other guy's output, by examining the insides of the monitor
system.  The output spy program was called OS.  Throughout the rest of
the computer science (and also at IBM) OS means "operating system",
but among old-time ITS hackers it almost always meant "output spy".

OS could work because ITS purposely had very little in the way of
"protection" that prevented one user from interfering with another.
Fair is fair, however.  There was another program that would
automatically notify you if anyone started to spy on your output.  It
worked in exactly the same way, by looking at the insides of the
operating system to see if anyone else was looking at the insides that
had to do with your output.  This "counterspy" program was called
JEDGAR (pronounced as two syllables: /jed'gr/), in honor of the former
head of the FBI.

But there's more. The rest of the story is that JEDGAR would ask the
user for "license to kill".  If the user said yes, then JEDGAR would
actually gun the job of the luser who was spying.  However, people
found this made life too violent, especially when tourists learned
about it.  One of the systems hackers solved the problem by replacing
JEDGAR with another program that only pretended to do its job.  It
took a long time to do this, because every copy of JEDGAR had to be
patched, and to this day no one knows how many people never figured
out that JEDGAR had been defanged.

Appendix B: A Portrait of J. Random Hacker

This profile reflects detailed comments on an earlier `trial balloon'
version from about a hundred USENET respondents.  Where comparatives
are used, the implicit `other' is a randomly selected group from the
non-hacker population of the same size as hackerdom.

General appearance:

Intelligent.  Scruffy.  Intense.  Abstracted.  Interestingly for a
sedentary profession, more hackers run to skinny than fat; both
extremes are more common than elswhere.  Tans are rare.


Casual, vaguely post-hippy; T-shirts, jeans, running shoes,
Birkenstocks (or bare feet).  Long hair, beards and moustaches are
common.  High incidence of tie-die and intellectual or humorous
`slogan' T-shirts (only rarely computer related, that's too obvious).

A substantial minority runs to `outdoorsy' clothing --- hiking boots
("in case a mountain should suddenly spring up in the machine room",
as one famous parody put it), khakis, lumberjack or chammy shirts and
the like.

Very few actually fit the National-Lampoon-Nerd stereotype, though it
lingers on at MIT and may have been more common before 1975.  These
days, backpacks are more common than briefcases, and the hacker `look'
is more whole-earth than whole-polyester.

Hackers dress for comfort, function, and minimal maintenance hassles
rather than for appearance (some, unfortunately, take this to extremes
and neglect personal hygiene).  They have a very low tolerance of
suits or other `business' attire, in fact it is not uncommon for
hackers to quit a job rather than conform to dress codes.

Female hackers never wear visible makeup and many use none at all.

Reading habits:

Omnivorous, but usually includes lots of science and science fiction.
The typical hacker household might subscribe to "Analog",
"Scientific American", "Co-Evolution_Quarterly" and
"Smithsonian".  Hackers often have a reading range that astonishes
`liberal arts' people but tend not to talk about it as much.  Many
hackers spend as much of their spare time reading as the average
American burns up watching TV, and often keep shelves and shelves of
well-thumbed books in their homes.

Other interests:

Some hobbies are widely shared and recognized as going with the
culture, including: science fiction.  Music (see the MUSIC entry).
Medievalism.  Chess, go, wargames and intellectual games of all kinds.
Role-playing games such as Dungeons and Dragons used to be extremely
popular among hackers but have lost a bit of their former luster as
they moved into the mainstream and became heavily commercialized.
Logic puzzles.  Ham radio.  Other interests that seem to correlate
less strongly but positively with hackerdom include: linguistics and
theater teching.

Physical Activity and Sports:

Many (perhaps even most) hackers don't do sports at all and are
determinedly anti-physical.

Among those that do, they are almost always self-competitive ones
involving concentration, stamina and micromotor skills; martial arts,
bicycling, kite-flying, hiking, rock-climbing, sailing, caving,

Hackers avoid most team sports like the plague (volleyball is a
notable and unexplained exception).


Nearly all hackers past their teens are either college-degreed or
self-educated to an equivalent level.  The self-taught hacker is often
considered (at least by other hackers) to be better-motivated and more
respected than his B.Sc. counterpart.  Academic areas from which
people often gravitate into hackerdom include (besides the obvious
computer science and electrical engineering) physics, mathematics,
electrical engineering, linguistics, and philosophy.

Things hackers detest and avoid:

IBM mainframes.  Smurfs and other forms of offensive cuteness.
Bureaucracies.  Stupid people.  Easy listening music.  Television
(except for cartoons, movies, the old _Star_Trek_ and the new
_Simpsons_).  Business suits.  Dishonesty.  Incompetence.  Boredom.
BASIC.  Character-based menu interfaces.


Ethnic.  Spicy.  Oriental, esp.  Chinese and most especially Szechuan,
Hunan and Mandarin (hackers consider Cantonese vaguely declasse).
Thai food has experienced flurries of popularity.  Where available
high-quality Jewish delicatessen food is much esteemed.  A visible
minority of Midwestern and Southwestern hackers prefers Mexican.

For those all-night hacks, pizza and microwaved burritos are big.
Interestingly, though the mainstream culture has tended to think of
hackers as incorrigible junk-food junkies, many have at least mildly
health-foodist attitudes and are fairly discriminating about what they
eat.  This may be generational; anecdotal evidence suggests that the
stereotype was more on the mark ten years ago.


Vaguely left of center, except for the strong libertarian contingent
which rejects conventional left-right politics entirely.  The only
safe generalization is that almost all hackers are anti-authoritarian,
thus both conventional conservatism and "hard" leftism are rare.
Hackers are far more likely than most non-hackers to either a) be
aggressively apolitical, or b) entertain peculiar or idiosyncratic
political ideas and actually try to live by them day-to-day.

Gender & Ethnicity:

Hackerdom is still predominently male.  However, the proportion of
women is clearly higher than the low-single-digit range typical for
technical professions.

Hackerdom is predominantly Caucasian with a strong minority of Jews
(east coast) and Asians (west coast).  The Jewish contingent has
exerted a particularly pervasive cultural influence (see Food, and
note that several common slang terms are obviously mutated Yiddish).

Hackers as a group are about as color-blind as anyone could ask for,
and ethnic prejudice of any kind tends to be met with extreme
hostility; the ethnic distribution of hackers is understood by them to
be a function of who tends to seek and get higher education.

It has been speculated that hackish gender- and color-blindness is
partly a positive effect of ASCII-only network channels.


Agnostic.  Atheist.  Non-observant Jewish.  Neo-pagan.  Very commonly
three or more of these are combined in the same person.  Conventional
faith-holding Christianity is rare though not unknown (at least on the
east coast, more hackers wear yarmulkes than crucifixes).

Even hackers who identify with a religious affiliation tend to be
relaxed about it, hostile to organized religion in general and all
forms of religious bigotry in particular.  Many enjoy `parody'
religions such as Discordianism and the Church of the SubGenius.

Also, many hackers are influenced to varying degrees by Zen Buddhism
or (less commonly) Taoism, and blend them easily with their `native'

There is a definite strain of mystical, almost Gnostic sensibility
that shows up even among those hackers not actively involved with
neo-paganism, Discordianism, or Zen.  Hacker folklore that pays homage
to `wizards' and speaks of incantations and demons has too much
psychological truthfulness about it to be entirely a joke.

Ceremonial chemicals:

Most hackers don't smoke tobacco and use alcohol in moderation if at
all (though there is a visible contingent of exotic-beer fanciers).
Limited use of `soft' drugs (esp. psychedelics such as marijuana, LSD,
psilocybin etc) used to be relatively common and is still regarded
with more tolerance than in the mainstream culture.  Use of `downers'
and opiates, on the other hand, appears to be particularly rare;
hackers seem in general to dislike drugs that `dumb them down'.  On
the other hand, many hackers regularly wire up on caffeine and sugar
for all-night hacking runs.

Communication style:

See the dictionary notes on `Hacker speech style'.  Though hackers
often have poor person-to-person communication skills, they are as a
rule extremely sensitive to nuances of language and very precise in
their use of it.  They are often better at written communication than

Geographical Distribution:

In the U.S., hackerdom revolves on a Bay Area/Boston axis; about half
of the hard core seems to live within a hundred miles of Cambridge or
Berkeley.  Hackers tend to cluster around large cities, especially
`university towns' such as the Raleigh/Durham area in North Carolina
or Princeton, New Jersey (this may simply reflect the fact that many
are students or ex-students living near their alma maters).

Sexual habits:

Hackerdom tolerates a much wider range of sexual and lifestyle
variation than the mainstream culture.  It includes a relatively large
gay contingent.  Hackers are more likely to live in polygynous or
polyandrous relationships, practice open marriage or live in communes
or group houses.  In this as in some other respects (see Dress)
hackerdom semi-consciously maintains `counterculture' values.

Personality Characteristics:

The most obvious common `personality' characteristics of hackers are
high intelligence, consuming curiosity, and facility with intellectual
abstractions.  Also, most hackers are `neophiles', stimulated by and
appreciative of novelty (especially intellectual novelty).  Most are
also relatively individualistic and anti-conformist.

Contrary to stereotype, hackers are *not* usually intellectually
narrow; they tend to be interested in any subject that can provide
mental stimulation, and can often discourse knowledegeably and even
interestingly on any number of obscure subjects --- assuming you can
get them to talk at all as opposed to, say, going back to hacking.

Hackers are `control freaks' in a way that has nothing to do with the
usual coercive or authoritarian connotations of the term.  In the same
way that children delight in making model trains go forward and back
by moving a switch, hackers love making complicated things like
computers do nifty stuff for them.  But it has to be *their*
nifty stuff; they don't like tedium or nondeterminism.  Accordingly
they tend to be careful and orderly in their intellectual lives and
chaotic elsewhere.  Their code will be beautiful, even if their desks
are buried in three feet of crap.

Hackers are generally only very weakly motivated by conventional
rewards such as social approval or money.  They tend to be attracted
by challenges and excited by interesting toys, and to judge the
interest of work or other activities in terms of the challenges
offered and the toys they get to play with.

In terms of Myers-Briggs and equivalent psychometric systems,
hackerdom appears to concentrate the relatively rare INTJ and INTP
types; that is, introverted, intuitive and thinker types (as opposed
to the extroverted-sensate personalities the predominate in the
mainstream culture).  ENT[JP] types are also concentrated among
hackers but are in a minority.

Weaknesses of the hacker personality:

Relatively little ability to identify emotionally with other people.
This may be because hackers generally aren't much like `other people'.
Unsurprisingly, there is also a tendency to self-absorption,
intellectual arrogance, and impatience with people and tasks perceived
to be wasting one's time.  As a result, many hackers have difficulty
maintaining stable relationships.

As cynical as hackers sometimes wax about the amount of idiocy in the
world, they tend at bottom to assume that everyone is as rational,
`cool', and imaginative as they consider themselves.  This bias often
contributes to weakness in communication skills.  Hackers tend to be
especially poor at confrontations and negotiation.

Hackers are often monumentally disorganized and sloppy about dealing
with the physical world.  Bills don't get paid on time, clutter piles
up to incredible heights in homes and offices, and minor maintenance
tasks get deferred indefinitely.

The sort of person who uses phrases like `incompletely socialized'
usually thinks hackers are.  Hackers regard such people with contempt
when they notice them at all.


Hackers are more likely to keep cats than dogs.  Many drive incredibly
decrepit heaps and forget to wash them; richer ones drive spiffy
Porsches and RX-7s and then forget to wash them.

Appendix C: Bibliography

Here are some other books you can read to help you understand the
hacker mindset.

     Godel, Escher, Bach: An Eternal Golden Braid
     Hofstadter, Douglas
     Basic Books, New York 1979
     ISBN 0-394-74502-7

This book reads like an intellectual Grand Tour of hacker
preoccupations.  Music, mathematical logic, programming, speculations
on the nature of intelligence, biology, and Zen are woven into a
brilliant tapestry themed on the concept of encoded self-reference.
The perfect left-brain companion to _Illuminatus_.

     Illuminatus (three vols)
         1.  The Golden Apple 
         2.  The Eye in the Pyramid
         3.  Leviathan
     Shea, Robert & Wilson, Robert Anton
     Dell Books, New York 1975
     ISBN 0-440-{14688-7,34691-6,14742-5}

This work of alleged fiction is an incredible berserko-surrealist
rollercoaster of world-girdling conspiracies, intelligent dolphins,
the fall of Atlantis, who really killed JFK, sex, drugs, rock and roll
and the Cosmic Giggle Factor.  First published in 3 volumes, but
there's now a one-volume trade paperback carried by most chain
bookstores under SF.  The perfect right-brain companion to Hofstadter's
"Godel, Escher, Bach: An Eternal Golden Braid".  See <Eris>,
<Discordianism>, <random numbers>, <Church Of The Sub-Genius>.

     The Hitchhiker's Guide to the Galaxy
     Douglas Adams
     Pocket Books 1981, New York
     ISBN 0-671-46149-4

This Monty-Python-in-Space spoof of SF genre traditions has been
popular among hackers ever since the original British radio show.
Read it if only to learn about Vogons (see <bogons>) and the
significance of the number 42 (see <random numbers>) --- also why the
winningest chess program of 1990 was called "Deep Thought".

     The Tao of Programming
     James Geoffrey
     Infobooks 1987, Santa Monica,
     ISBN 0-931137-07-1

This gentle, funny spoof of the "Tao Te Ching" contains much that is
illuminating about the hacker way of thought. "When you have learned
to snatch the error code from the trap frame, it will be time for you
to leave."

     Steven Levy
     Anchor/Doubleday 1984, New York
     ISBN 0-385-19195-2

Levy's book is at its best in describing the early MIT hackers at the
Model Railroad Club and the early days of the microcomputer
revolution.  He never understood UNIX or the networks, though, and his
enshrinement of Richard Stallman as "the last true hacker" turns out
(thankfully) to have been quite misleading.

     The Cuckoo's Egg
     Clifford Stoll
     Doubleday 1989, New York
     ISBN 0-385-24946-2

Clifford Stoll's absorbing tale of how he tracked Markus Hess and the
Chaos Club cracking-ring nicely illustrates the difference between
`hacker' and `cracker'.  And Stoll's portrait of himself and his lady
Barbara and his friends at Berkeley and on the Internet paints a
marvelously vivid picture of how hackers and the people around them
like to live and what they think.

     The Devil's DP Dictionary
     by Stan Kelly-Bootle
     McGraw-Hill Inc, 1981
     ISBN 0-07-034022-6

This pastiche of Ambrose Bierce's famous work is similar in format to
the Jargon File (and quotes several entries from jargon-1) but
somewhat different in tone and intent.  It is more satirical and less
anthropological, and largely a product of the author's literate and
quirky imagination.  For example, it defines "computer science" as
"A study akin to numerology and astrology, but lacking the precision
of the former and the success of the latter"; also as "The boring
art of coping with a large number of trivialities."

     The Devouring Fungus: Tales from the Computer Age
     by Karla Jennings
     W.  W. Norton 1990, New York
     ISBN 0-393-30732-8

The author of this pioneering compendium knits together a great deal
of computer and hacker-related folklore with good writing and a few
well-chosen cartoons.  She has a keen eye for the human aspects of the
lore and is very good at illuminating the psychology and evolution of
hackerdom.  Unfortunately, a number of small errors and awkwardnesses
suggest that she didn't have the final manuscript vetted by a hackish
insider; the glossary in the back is particularly embarrassing, and at
least one classic tale (the Magic Switch story in this file's Appendix
A) is given in incomplete and badly mangled form.  Nevertheless, this
book is a win overall and can be enjoyed by hacker and non-hacker

     True Names...and Other Dangers
     by Vernor Vinge
     Baen Books 1987, New York
     ISBN 0-671-65363

Hacker demigod Richard Stallman believes the title story of this book
"expresses the spirit of hacking best".  This may well be true; it's
certainly difficult to recall anyone doing a better job.  The other
stories in this collection are also fine work by an author who is
perhaps one of today's very best practitioners of the hard-SF genre.