A hidden element written into a program or placed on a Web site. Basically, it is a special feature that is not otherwise made obvious, but when "clicked on," it offers something special. This could be in the form of an extra game level or a secret area or an animation or a surprise image of some kind. Programmers often "bury" easter eggs in their programs to add a certain extra depth to the program and to challenge their users to find it.
NetLingo Classification: Online Jargon