MUCK

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.

MUCKs are extensible by design, players can create and modify ("build") all internal objects of the game environment, including rooms, exits, and even the system commands, for which the MUCKs use the MUF (Multi-User Forth) language. Fuzzball MUCKs also use Message Parsing Interpreter (MPI) which can be used to embed executable code into descriptions of all in-game objects. Unlike many other virtual worlds, however, TinyMUCK and its descendents do not usually have computer-controlled monsters for players to kill.

TinyMUCKs are popular among members of furry fandom; examples of active, large TinyMUCKs include FurryMUCK and Tapestries MUCK, both of which run the Fuzzball version of MUCK server code. A MUCK was very popular during the 1980s and 1990s at Digital Equipment Corporation. A frontend consisting of full command line editing as well as server side scripts was available at DEC called MUCKER, written by an employee Philip Hunt.

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