adjective

• elite; COOL. "Hacker code," in which 1 is "L", 3 is "E", and 7 is "T".

  Man, that's one 1337 computer!

  by Matthew B., Charleston, WV, USA, Feb 13 2002.

adjective

• missing or misplaced.

  My car keys are 404.

  by Eric B., Fort Worth, TX, USA, Aug 10 1998.

noun

• an unintelligent person; MORON, DIMWIT.

  I wouldn't ask him, he's a 404.

  by Walt W., Natick, Massachusetts, USA, Jun 17 2003.

• a worthless person, place, or thing.

  Don't go to that bar - it's a 404.

  by Robbie G., Stroud, Hampshire, UK, Feb 13 2006.

verb

• to not know or temporarily forget; DRAW A BLANK.

  I'm 404ing on that.

  by The Jargon File, Aug 04 2009.

origin

• 404 is the web code for "web page not found."

  by Anonymous, Jul 17 2007.

interjection

• as a question, to enquire whether someone is present.

  Speaker: ACK?
  
  Response: ACK.

  by Anonymous, Sep 28 2008.

• to affirm one's presence. An appropriate response to ping.

  Speaker: Are you there?
  
  Response: ACK.

  Speaker: ping
  
  Response: ACK.

  by Anonymous, Sep 28 2008.

• an exclamation of surprise or alarm.

  Ack!

  by Anonymous, Sep 28 2008.

• yes.

  Speaker: Do you want to shop for monitors?
  
  Response: ACK.

  by Anonymous, Sep 28 2008.

origin

• ACK is an abbreviation of "acknowledged," used commonly in computing. See also NAK. Note that "ack" as an exclamation of surprise or alarm has no relation to computing.

  by The Jargon File, Sep 28 2009.

other

• acronym of "as far as I know." Commonly used online.

  AFAIK, the store is still open.

  by Anonymous, Jul 17 2007.

other

• acronym of "away from keyboard." Commonly used in online chats. Typically one "goes" AFK, as in the following sentence. One can also use AFK to respond to a message, indicating that one isn't currently available for chatting.

  I need to go AFK to make a phone call.

  Chatter: Hey, are you around?
  
  Response: AFK.

  by The Jargon File, Jul 17 2009.

expression

• declaration of victory or superiority.

  by Anonymous, Jul 17 2007.

origin

• The 1991 Sega Genesis video game "Zero Wing." Its introduction has what many consider to be the worst Japanese-to-English translation in video game history. It shows the bridge of a starship in chaos as the enemy appears and says, "How are you gentlemen!! All your base are belong to us."
  
  In 2001, this mistranslation spread virally through the Internet, bringing with it a slew of images of doctored photographs, each showing a street sign, store front, package label, etc. manipulated to read "All your base are belong to us."
  
  The original has been generalized to "All your X are belong to us", to connote a sinister takeover of some thing "X." For example:

  When Joe signed up for his new job at Yoyodyne, he had to sign a draconian non-disclosure agreement. It basically said, "All your thoughts are belong to us."

  by The Jargon File, Jul 17 2009.

other

• online chatting acronym of "age, sex, location?" An inquiry of one's age, gender, and location.

  Hey disco! ASL?

  by Farah, NJ, USA, Apr 28 2002.

adverb

• to happen automatically. Implies that the observer has no understanding of the mechanism of action, such that it appears almost magical.

  Windows users thinks everything happens automagically.

  by Allen G., Dec 18 2000.

• Automatically, but in a way that, 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.

  by The Jargon File, Apr 17 2009.

origin

• This term is quite old, going back at least to the mid-70s in jargon and probably much earlier. The word "automagic" occurred in advertising (for a shirt-ironing gadget) as far back as the late 1940s.

  by The Jargon File, Apr 17 2009.

noun

• an icon, pictorial, or 3D representation of a person online. In the online gaming community, for example, one's character as seen by other players is one's avatar. Origin: in Hindu mythology, an avatar is a physical incarnation of a deity on earth.

  Her game avatar was getting its butt kicked.

  by Ray G., Seattle, WA, USA, Jan 12 2003.

adverb

• before. Online chat acronym.

  I knew you B4 we went to the same school together.

  by Maurice J., Fall River, MA, USA, Nov 21 2002.