: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. [from the comic strip "Bloom County">[ An exclamation of surprised disgust, esp. in "Ack pffft!" Semi-humorous. Generally this sense is not spelled in caps (ACK) and is distinguished by a following exclamation point. 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".

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").

: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. For example, fuzzy-matching input tokens that might be typing errors against a symbol table can make it look as though a program knows how to spell. 2. Special-case code to cope with some awkward input that would otherwise cause a program to {choke}, presuming normal inputs are dealt with in some cleaner and more regular way. Also called `ad-hackery', `ad-hocity' (/ad-hos'*-tee/), `ad-crockery'. See also {ELIZA effect}.

:Ada:: n. A {{Pascal}}-descended language that has been made mandatory for Department of Defense software projects by the Pentagon. Hackers are nearly unanimous in observing that, technically, it is precisely what one might expect given that kind of endorsement by fiat; designed by committee, crockish, difficult to use, and overall a disastrous, multi-billion-dollar boondoggle (one common description is "The PL/I of the 1980s"). Hackers find Ada's exception-handling and inter-process communication features particularly hilarious. Ada Lovelace (the daughter of Lord Byron who became the world's first programmer while cooperating with Charles Babbage on the design of his mechanical computing engines in the mid-1800s) would almost certainly blanch at the use to which her name has latterly been put; the kindest thing that has been said about it is that there is probably a good small language screaming to get out from inside its vast, {elephantine} bulk.

:adger: /aj'r/ [UCLA] vt. To make a bonehead move with consequences 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}.

:admin: /ad-min'/ n. Short for `administrator'; very commonly used in speech or on-line to refer to the systems person in charge on a computer. Common constructions on this include `sysadmin' and `site admin' (emphasizing the administrator's role as a site contact for email and news) or `newsadmin' (focusing specifically on news). Compare {postmaster}, {sysop}, {system mangler}.

: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 permitted only 6-letter filenames. See also {vadding}.

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 some noun X). "You are in a maze of twisty little passages, all alike." "You are in a little maze of twisty passages, all different." 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.

:AFJ: n. Written-only abbreviation for "April Fool's Joke". Elaborate April Fool's hoaxes are a hallowed tradition on USENET and Internet; see {kremvax} for an example. In fact, April Fool's Day is the *only* seasonal holiday marked by customary observances on the hacker networks.