(mud)

Basically, a cyber-environment where users assume the identity of an avatar to interact. MUDs started as multi-user games but these have evolved into much more extensive environments which can include 3D and chat. Often you can visit a MUD as a guest before joining.

MUDs, and their derivatives, come from a 1979 hack of the University of Essex's DEC-10 computer by Richard Bartle and Roy Trubshaw. They created a game similar to the old classic Colossal Cave but with multiple users and interaction (you might run into a BartleMUD which derives from this original). The term MUD was placed into the public domain by Bartle in 1985 (despite a rumor to the contrary that sometimes circulates).

Any MUD player who is completely absorbed by the game is termed a "mudhead." MUDs can be addictive.

More Information

• MUD FAQ