MUD/MUD1
British Legends, originally known as Multi-User Dungeon, or MUD (referred to as MUD1, to distinguish it from its successor, MUD2, and the MUD genre in general) is the first MUD and the oldest online game in existence. It was created in 1978 by Roy Trubshaw at Essex University on a DEC PDP-10 in the UK, using the MACRO-10 Assembler language. He named the game Multi-User Dungeon, in tribute to the Dungeon variant of Zork, which Trubshaw had greatly enjoyed playing. Zork in turn inspired an influential text-adventure game known as Colossal Cave Adventure, or ADVENT. In 1980 Roy Trubshaw created MUD version 3 in BCPL (the predecessor of C), to conserve memory and make the program easier to maintain. Richard Bartle, a fellow Essex student, contributed much work on the game database, introducing many of the locations and puzzles that survive to this day. Later that year Roy Trubshaw graduated from Essex University, handing over MUD to Richard Bartle, who continued developing the game. That same year, MUD1 became the first multiplayer online role-playing game as Essex University connected its internal network to the ARPANET.
In 1983 Essex University allowed remote access to its DEC-10 via British Telecom's Packet Switch Stream network between 2AM and 7AM each night. MUD became popular with players around the world, and several magazines wrote articles on this new trend. In 1984 Compunet, a France-based system primarily for Commodore 64 users, licensed MUD1 and ran it from late 1984 until 1987, when CompuNet abandoned the DEC-10 platform they were using. In 1985 Richard Bartle created MUD1 version 4, better known as MUD2. It was intended to be run as a service for British Telecom. In 1987 MUD1 was licensed by CompuServe, who pressured Richard Bartle to close down the instance of MUD1, better known as 'Essex MUD', that was still running at Essex University. This resulted in the deletion of the MUD account in October 1987. MUD1 ran under the name "British Legends" until late 1999 and was retired along with other software during CompuServe's Y2K cleanup efforts.