Last updated
Developer(s) Sebastian Hammer, Michael Seifert, Hans Henrik Stærfeldt, Tom Madsen, Katja Nyboe
Platform(s) Unix-like
  • WW: 1 March 1991
Genre(s) MUD
Mode(s) Multiplayer

DikuMUD is a multiplayer text-based role-playing game, which is a type of MUD. It was written in 1990 and 1991 by Sebastian Hammer, Tom Madsen, Katja Nyboe, Michael Seifert, and Hans Henrik Stærfeldt at DIKU (Datalogisk Institut Københavns Universitet)—the department of computer science at the University of Copenhagen in Copenhagen, Denmark. [1] [2]

A MUD is a multiplayer real-time virtual world, usually text-based. MUDs combine elements of role-playing games, hack and slash, player versus player, interactive fiction, and online chat. Players can read or view descriptions of rooms, objects, other players, non-player characters, and actions performed in the virtual world. Players typically interact with each other and the world by typing commands that resemble a natural language.

Computer science study of the theoretical foundations of information and computation

Computer science is the study of processes that interact with data and that can be represented as data in the form of programs. It enables the use of algorithms to manipulate, store, and communicate digital information. A computer scientist studies the theory of computation and the practice of designing software systems.

University of Copenhagen public research university in Copenhagen, Denmark

The University of Copenhagen (UCPH) is the oldest university and research institution in Denmark. Founded in 1479 as a studium generale, it is the second oldest institution for higher education in Scandinavia after Uppsala University (1477). The university has 23,473 undergraduate students, 17,398 postgraduate students, 2,968 doctoral students and over 9,000 employees. The university has four campuses located in and around Copenhagen, with the headquarters located in central Copenhagen. Most courses are taught in Danish; however, many courses are also offered in English and a few in German. The university has several thousands of foreign students, about half of whom come from Nordic countries.


Commonly referred to as simply "Diku", the game was greatly inspired by AberMUD, [1] [3] though Diku became one of the first multi-user games to become popular as a freely-available program for its gameplay and similarity to Dungeons & Dragons . The gameplay style of the great preponderance of DikuMUDs is hack and slash, which is seen proudly as emblematic of what DikuMUD stands for. [4]

AberMUD was the first popular open source MUD. It was named after the town Aberystwyth, in which it was written. The first version was written in B by Alan Cox, Richard Acott, Jim Finnis, and Leon Thrane based at University of Wales, Aberystwyth for an old Honeywell mainframe and opened in 1987.

<i>Dungeons & Dragons</i> fantasy role-playing board game

Dungeons & Dragons is a fantasy tabletop role-playing game (RPG) originally designed by Gary Gygax and Dave Arneson. It was first published in 1974 by Tactical Studies Rules, Inc. (TSR). The game has been published by Wizards of the Coast since 1997. It was derived from miniature wargames, with a variation of the 1971 game Chainmail serving as the initial rule system. D&D's publication is commonly recognized as the beginning of modern role-playing games and the role-playing game industry.

Hack and slash or hack and slay refers to a type of gameplay that emphasizes combat.

Diku's source code was first released in 1990. [5]

Development and history

The making of DikuMUD was first announced on Usenet by Hans Henrik Stærfeldt March 27, 1990. At the time Tom Madsen, Sebastian Hammer, and Stærfeldt were the only developers, joined by Michael Seifert in June 1990. Stærfeldt stated that their intention was to create a MUD that was less messy than AberMUD, less buggy than LPMud, and more like Dungeons & Dragons . [6]

LPMud, abbreviated LP, is a family of MUD server software. Its first instance, the original LPMud game driver, was developed in 1989 by Lars Pensjö. LPMud was innovative in its separation of the MUD infrastructure into a virtual machine and a development framework written in the LPC programming language.

The first DikuMUD was in working development as early as October 1990 and officially opened publicly running at freja.diku.dk port 4000 on February 3, 1991. [7]

A second DikuMUD appeared in January 1991, running at hayes.ims.alaska.edu. [8] In March 1991, the first public version of DikuMUD, known as Diku Gamma, became available at beowulf.acc.stolaf.edu. Afterwards the DikuMUD at freja.diku.dk was shut down and the game and development moved to alfa.me.chalmers.se. [9]

Other Diku Gamma MUDs appeared in March 1991 running at eris.berkeley.edu, followed by a multiprocessor version running at sequent.berkeley.edu. [10] By early April 1991, there were DikuMUDs running at spam.ua.oz.au, goldman.gnu.ai.mit.edu, bigboy.cis.temple.edu, and elof.iit.edu.

The last official release of DikuMUD was Diku Alfa in July 1991 and the DikuMUD team hereafter continued with the development of DikuII. That version was however never released to the public but continues to run today under the name of Valhalla MUD. [11]

DikuMUD license

The DikuMUD license is generous, but does not permit all possible uses. The source code for DikuMUD is publicly available at no charge, anyone can run an unmodified or modified DikuMUD without paying any royalties, and modified derivatives of the DikuMUD code can be publicly distributed. However, the DikuMUD license includes the following requirement: "You may under no circumstances make profit on *ANY* part of DikuMud in any possible way. You may under no circumstances charge money for distributing any part of dikumudthis includes the usual $5 charge for 'sending the disk' or 'just for the disk' etc." [12] Thus, DikuMUD is not open-source software as defined by the Open Source Definition (OSD), because the OSD's clause 6 requires "No Discrimination Against Fields of Endeavor", that is, commercial users cannot be excluded. For the same reason, DikuMUD is not Free Software as per the Free Software Definition. However, DikuMUD and its derivatives are developed in the same manner as these similar software production practices.


In his book Designing Virtual Worlds , Richard Bartle (co-creator of the original MUD) cited DikuMUD as one of the five "major codebases used for (textual) virtual worlds". Bartle further described how DikuMUD went in the opposite direction to TinyMUD and LPMud, by providing a very well organised hard-coded game that ran "out of the box". [13]

It has been proposed by Raph Koster (lead designer of Ultima Online and chief creative officer of EverQuest II ) that Diku has resulted in the greatest proliferation of gameworlds due to being the easiest to set up and use. [14] [15] He further pointed out that "Diku codebases did eventually popularize many of the major developments in muds", [16] and that the Diku gameplay provided inspiration for numerous MMORPGs, including EverQuest , World of Warcraft and Ultima Online . [17]

EverQuest controversy

There was a minor controversy in late 1999 and early 2000 regarding whether the commercial MMORPG EverQuest , developed by Verant Interactive, had derived its code from DikuMUD. [18] It began at the Re:Game gaming conference in 1999, where the Director of Product Development for EverQuest, Bernard Yee, allegedly stated that EverQuest was "based on Dikumud". He did not specify whether he meant the code itself was derived from DikuMUD, or if it just had a similar feeling. Some attendees had understood it to mean the former and reported to that effect on Usenet. [19] After the Diku group requested clarification, Verant issued a sworn statement on March 17, 2000 that EverQuest was not based on DikuMUD source code, and was built from the ground up. [20] [21] In response, the DikuMUD team publicly stated that they find no reason whatsoever to believe any of the rumors that EverQuest was derived from DikuMUD code. [22]

See also

Related Research Articles

<i>BatMUD</i> 1990 video game

BatMUD is a medieval fantasy MUD, established in 1990. BatMUD is Finland-based and operated and owned by a non-profit organization, Balanced Alternative Techniques ry, officially registered 1994 in Helsinki, Finland.

The UCPH Department of Computer Science is a department under the Faculty of Science at University of Copenhagen (UCPH). DIKU offers both undergraduate, graduate and Ph.D. programs. Students with a diploma equivalent of a Danish secondary school diploma are accepted for the undergraduate program, from where they can proceed with graduate studies and eventually Ph.D. studies.

<i>Ancient Anguish</i> 1992 video game

Ancient Anguish, abbreviated AA, is a fantasy-themed MUD, a text-based online role-playing game. Founded in 1991 by Balz "Zor" Meierhans and Olivier "Drake" Maquelin, it opened to the public on February 2, 1992. It is free-to-play, but has been supported by player donations since 1994.

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A MUD client is a computer application used to connect to a MUD, a type of multiplayer online game. Generally, a MUD client is a very basic telnet client that lacks VT100 terminal emulation and the capability to perform telnet negotiations. On the other hand, MUD clients are enhanced with various features designed to enhance the gameplay of MUDs.

MudOS is a major family of LPMud server software, implementing its own variant of the LPC programming language. It first came into being on February 18, 1992. It pioneered important technical innovations in MUDs, including the network socket support that made InterMUD communications possible and LPC-to-C compilation. Its name reflects its focus on separation of concerns between game driver and mudlib. FluffOS is Discworld MUD's fork of MudOS, and still being developed.

Lars Pensjö of Sweden is the original author of the LPMud MUD engine and the LPC programming language, and is one of the founders of Genesis LPMud, notable for their part in the history of MMORPGs as well as the Pike programming language. He attended Chalmers University of Technology in Gothenburg, Sweden, from 1980 to 1984. He was a member of the as of 2008 defunct Chalmers Datorförening ("CD"), after which the CD gamedriver and mudlib were named.

Merc is a MUD engine derived from Copper, which in turn was based on DikuMUD. First released in March 1991, DikuMUD served as the basis for many later MUDs.

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Raphael "Raph" Koster is an American entrepreneur, game designer, and author of A Theory of Fun for Game Design. Koster is widely recognized for his work as the lead designer of Ultima Online and the creative director behind Star Wars Galaxies. From 2006 until 2013 he worked as the founder and president of Metaplace producing a Facebook game platform.

Mob (gaming) in an MMORPG or MUD, an NPC that is hostile and/or vulnerable to attack, especially generic monstrous NPCs that the player is expected to hunt and kill, but excluding those that engage in dialog, sell items, or which cannot be attacked

A mob, short for mobile, also known as an enemy or mook, is a computer-controlled non-player character (NPC) in a computer game such as an MMORPG or MUD. Depending on context, every and any such characters in a game may be considered to be a "mob", or usage of the term may be limited to hostile NPCs and/or NPCs vulnerable to attack. Common usage refers to either a single character or a multitude of characters in a group as a mob.

TinyMUCK or, more broadly, a MUCK, is a type of user-extendable online text-based role-playing game, designed for role playing and social interaction. Backronyms like "Multi-User Chat/Created/Computer/Character/Carnal Kingdom" and "Multi-User Construction Kit" are sometimes cited, but are not the actual origin of the term; "muck" is simply a play on the term MUD.

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  1. 1 2 Shah, Rawn; Romine, James (1995). Playing MUDs on the Internet. John Wiley & Sons, Inc. p. 22. ISBN   0-471-11633-5. DikuMud first appeared in mid-March of 1990 when a group of programmers at the Department of Computer Science at the University of Copenhagen, Denmark got together and began work on a multiplayer game that is similar to but improved on AberMuds. These coders were Hans Henrik Stærfeldt, Katja Nyboe, Tom Madsen, Michael Seifert, and Sebastian Hammer.
  2. Hahn, Harley (1996). The Internet Complete Reference (2nd ed.). Osborne McGraw-Hill. p. 558. ISBN   0-07-882138-X. DikuMuds are named after the Datalogisk Institut Københavns Universitet (Department of Computer Science, University of Copenhagen), where the original DikuMud was created in 1990 by Katja Nyboe, Tom Madsen, Hans Henrik Stærfeldt, Michael Seifert and Sebastian Hammer.
  3. Keegan, Martin (2003-02-02). "A Classification of MUDs". Martin Keegan's Home Page. Retrieved 2010-09-20.
  4. Shah, Rawn; Romine, James (1995). Playing MUDs on the Internet. John Wiley & Sons, Inc. p. 22. ISBN   0-471-11633-5. There are Muds for socializing and for being creative, but DikuMuds are for adventure, advancement, and battle.
  5. Mulligan, Jessica; Patrovsky, Bridgette (2003). Developing Online Games: An Insider's Guide. New Riders. pp. 452–453. ISBN   1-59273-000-0. 1990 [...] DIKU MUDs are released.
  6. Staerfeldt, Hans Henrik (1990). "New mud comming up.. [sic]". alt.mud. We have started to program a mud, that we hope will be finished some time in the end of the summer. This mud will be better (we hope) than other muds as we have learned from their mistakes.
  7. Hammer, Sebastian (1991). "New Mud". rec.games.mud. We consider playing in groups to be one of the more important (entertaining, that is) aspects of mudding, and hence the game includes various features, especially designed to make group-adventuring more fun and rewarding: Four different classes of players, with various abilities; a system which allows members of a group to share the score made at a kill; and lots of other stuff.
  8. Woodcock, Bruce Sterling (1991). "Mud List: January 31, 1991". rec.games.mud.
  9. Wisdom, Joseph (1990). "Arki's MUDLIST... promotional posting". rec.games.mud. beowulf.acc.stolaf.edu /pub/pub/mud tinymud, tinymuck, login style abermud, lpmud, ubermud, myth, ftp daemon patch for lpmuds, vast array of clients, gb, bt, dikumud.
  10. Wisdom, Joseph (1991). "MUD List". rec.games.mud. dikumud.
  11. "DikuMUD II running as Valhalla MUD" . Retrieved 2013-01-12.
  12. "DIKU mud". Virtual Worldlets Network. Retrieved 2010-04-06.
  13. Bartle, Richard (2003). Designing Virtual Worlds . New Riders. ISBN   0-13-101816-7.
  14. Koster, Raph (2007-05-29). "MMO long tails". Raph Koster's Website. Retrieved 2010-09-20.
  15. Koster, Raph. "LP Muds versus Diku-derived muds". Raph Koster's Website. Retrieved 2010-09-20.
  16. Koster, Raph (2009-01-09). "What is a Diku?". Raph Koster's Website. Retrieved 2010-09-20.
  17. Koster, Raph (2006-06-16). "From the mailbag: fan mail, UO, ideas". Raph Koster's Website. Retrieved 2010-09-20.
  18. Bartle, Richard (2003). Designing Virtual Worlds . New Riders. p. 25. ISBN   0-13-101816-7. If ever there was a case of being in the right place at the right time, EverQuest (EQ) is it. It was basically a DikuMUD with a graphical client bolted on - the similarities are so close that under legal threat its server programmers were forced to sign sworn statements to the effect that they didn't use any actual DikuMUD code in EverQuest.
  19. "Sony's EverQuest admits to using Diku as a base". rec.games.mud.diku. Retrieved 2007-02-03.
  20. Smedley, John; McQuaid, Brad (2000-03-17). "Sworn Statement". DIKU MUD. Archived from the original on 2011-04-13. Retrieved 2010-04-26.
  21. McQuaid, Brad; Clover, Steve; Uzun, Roger (2000-03-17). "Sworn Statement". DIKU MUD. Archived from the original on 2011-04-13. Retrieved 2010-04-26.
  22. "DikuMUD's statement on Everquest". Archived from the original on 2007-02-03. Retrieved 2007-02-03.

Further reading