Server Family: DikuMud
Language: C
Current version: Alfa
Status: Defunct.
Primary Website: http://www.dikumud.com.

DIKU mud, is a MUD, or Multi User Domain. Created in 1990 and 1991 by Sebastian Hammer, Tom Madsen, Katja Nyboe, Michael Seifert, and Hans Henrik Staerfeldt at DIKU, (Datalogisk Institut Københavns Universitet), the department of computer science at the University of Copenhagen in Copenhagen, Denmark.

Taking its name directly from the department, and known as just DIKU in general, this MUD codebase formed - and continues to form - the backbone of the MUDding community, with almost every mud codebase since, based off of it, after the source code was released free for non-profit use in 1991.

The Diku Family Tree

 ____________________________________DikuMUD_________________________ 
 |        |         |         |         |         |         |        |
Vie1     Silly    Pirate    Circle1   Diku_II   Sequent   Techno   Crimson
  |        |                   |                   |   
Vie2    DaleMUD       ______Circle2______       Copper1
  |                  |         |         |         |
Vie3            Archipelago Circle3  LostLands  Copper2____________
  |                                                |               |
Vie4                            _________________Merc1_______   Copper3
  |                            |                   |         |
Vie5                         Rom1                  |        Vego
                               :_________________Merc2________________
                               |         |         |         |        |
         ___________________Rom2.3   TheIsles    Envy1     SMAUG      ACK
        |         |            |      (NiMUD)      |         |
     Sunder   EmberMUD   ___Rom2.4___           _Envy2_    AFKMud
                        |      |     |         |       |
                   Anatolia  ROT  Oblivion  Mythran   EOS
                                     |
                               Dawn of Time

The Diku license does not permit unrestricted use. In an early parody of the GPL license, the Diku license includes the following requirement: "You may under no circumstances make profit on *ANY* part of Diku in any possible way. You may under no circumstances charge money for distributing any part of Diku - this includes the usual $5 charge for 'sending the disk' or 'just for the disk' etc."

This has filtered down to all derivative codebases, such that anyone considering a commercial MUD, or any other textual, interactive platform, cannot consider any of the above codebases, as all are influenced by the original Diku license.

Diku was not he first MUD, that honour lays with 'British Legends' in 1979. However, it was one of the first to become truly popular, and addictive. Diku was the first serious attempt to bring Dungeons and Dragons to the multiplayer online environment, and as such, it secured a strong following.

The mechanics for Diku proved so good that EverQuest adopted them, as the basis for that massively multiplayer RPG.

The last official release of Diku was Diku Alfa in July 1991.