Multiple User Dungeon

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A MUD, or Multiple User Dungeon, was "a space inside a computer, like a map in a game of D&D". Using typed-in commands, the users could walk from room to room, look at what was there, and communicate with other users. The MUD program "ran everything", and described the results of actions with text.

People could create characters that could represent them in the imaginary world, and give them pseudonyms. At least some MUDs were set up so that "guests" could appear as "anonymous wraiths" in public areas of the game. Normally, participants would go to great lengths to create their appearance.

In 1982, in an attempt to convince Sarah Swan to give up the Savant, the Sixth Doctor arranged a meeting with her inside a MUD. He used the pseudonym "Merryman", Swan called her character "Fionnuala", and Luis Perez, who joined the conversation later, used just "Luis". (PROSE: Blue Box ^[+]Loading...{"chapt":"70 Two","1":"Blue Box (novel)"})