Easter egg (virtual)

An Easter egg is an intentional inside joke, a hidden message, or a secret feature of an interactive work (often, a computer program, video game or DVD menu screen). The name is used to evoke the idea of a traditional Easter egg hunt.

Atari's 1979 release Adventure contains the first hidden message in a video game to have been discovered by its players; the message is "Created by Warren Robinett", and was inserted by Robinett, the game's programmer. According to Robinett, the term Easter egg was applied by Atari personnel on being alerted to the secret addition, and making the comparison of players' discovery of these secrets akin to the traditional Easter egg hunt.

In 2004, an earlier Easter egg was found in Video Whizball, a 1978 game for the Fairchild Channel F system, displaying programmer Bradley Reid-Selth's surname.

In computer software, Easter eggs are secret responses that occur as a result of an undocumented set of commands. The results can vary from a simple printed message or image, to a page of programmer credits or a small video game hidden inside an otherwise serious piece of software. Video game cheat codes are a specific type of Easter egg, in which entering a secret command will unlock special powers or new levels for the player. The first Easter egg to be found in a video game is the 1979 Adventure, which includes a secret room only accessible through a complicated series of gameplay steps. The secret room displays the message "Created by Warren Robinett". Because Atari did not publicly credit game designers, Robinett inserted the message after the game's completion partially in an attempt to gain some recognition for his work. The egg was discovered by a 15-year-old player in 1980, who wrote to Atari to tell them that he had found "something strange" in the game.

In the TOPS-10 operating system (for the DEC PDP-10 computer), the make command is used to invoke the TECO editor to create a file; if given the file name argument love, so that the command is make love, it will pause and respond not war? before creating the file. This same behavior occurred on the RSTS/E operating system, where TECO will provide this response. Other Unix operating systems respond to "why" with "why not" (a reference to The Prisoner in Berkeley Unix 1977).

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