MUD--Multiple-User Dungeon, Dimension, or Domain: a text-based virtual
reality run as a program on a large server computer in which characters,
created through programming code and textual description authored by the
users, interact in real-time with other characters and with objects and
places also created through textual description and programming code. The
acronym first stood for Multi-User Dungeon, since MUDs originated as
computerized versions of the role-playing adventure game Dungeons and
Dragons, which was popular on college campuses during the 1970's. The first
MUD was programmed by students at the University of Essex in England in
1979. Although MUD is hardly ever spelled out, the terms Domain and
Dimension tend to be adopted as politic euphemisms when explaining the
acronym by those who run MUDs or their descendants for educational
purposes. True MUDs differ in various significant ways from MUSHes, MOOs,
MUCKs and other text-based virtual realities descended from MUDs, but the
term MUD is often employed as a generic to refer to all text-based virtual
realities. In spelling derivatives, such as MUDding, MUDdom, or MUDsex, the
capitalization of the original is normally maintained.