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. The term was coined to describe a hidden message in the Atari video game Adventure that led Atari to encourage further hidden messages in later games, treating them as Easter eggs for players to find.

While not the first use of an hidden message in a work, the origin of the term "Easter egg" to describe these originated from the 1979 video game, Adventure for the Atari 2600. The game was programmed by Atari employee Warren Robinett. At the time, Atari would not include programmers' names in the game's credits, fearing that competitors would attempt to steal away their employees. Robinett, who had some issues with his supervisor over this and other issues at the time, secretly inserted the message "Created by Warren Robinett", which would only be triggered if the player moved their avatar over a single pixel (the "Gray Dot") in a certain part of the game. Robinett had not told anyone at Atari about this by the time he left the company. Shortly after his departure, the Gray Dot and his message was discovered by a player, who wrote their discovery into Atari. Atari's management initially wanted to reprogram and rerelease the game to remove the message, but this was a costly effort. Steve Wright, the director of software development of the Atari Consumer Division at the time, suggested that they keep the message and encourage future games to include such messages, describing these as Easter eggs for consumers to find, and thus coining the term.

Robinett's addition of his name to Adventure (1979) is recognized as the first well-known Easter egg, as well as the origin of the term. However, Robinett's Easter egg is not the first to be implemented. 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. According to research by Ed Fries, the first known Easter egg in arcade games came from Starship 1, programmed by Ron Milner and released in 1977, although its existence wasn't published until 2017. By triggering the cabinet's controls in the right order, the player could get the message "Hi Ron!" displayed to them on the screen. Fries described it as "the earliest arcade game yet known that clearly meets the definition of an Easter egg", and suggested that as more than one hundred arcade games predate Starship 1, earlier Easter eggs may still be undiscovered. Fries noted that some Atari arcade cabinets were resold under the Kee Games label, and included easily-implemented changes on the hardware that would make the game appear different for Kee; Anti-Aircraft II, released in 1975, included a means to modify the circuit board to make the airplanes in the game appear as alien UFOs, which Fries surmised would have been for a Kee Games' release, but argued if this is a true Easter egg since it requires hardware modification.

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