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What is a MUD?
A MUD is a Multi User something or other starting with D. Nobody's entirely sure what that D word is, but most people think it's either Dungeon, Dimension or Domain. Although any game or chat room fits this description, when people refer to a MUD they are almost always referring to a set of text based MMORPG's run over telnet. They have been in existence since the early 1980's with varying popularity - some of the most popular MUDs have over 500 players online during peak hours.