Mudding: Social Phenomena in Text-Based Virtual Realities
A MUD (Multi-User Dungeon or, sometimes, Multi-User Dimension) is a
network-accessible, multi-participant, user-extensible virtual reality whose
user interface is entirely textual. Participants (usually called players) have
the appearance of being situated in an artificially-constructed place that also
contains those other players who are connected at the same time. Players can
communicate easily with each other in real time.