What is a MUD?

A MUD (Multi User Dungeon) is a computer program which users can log into, and in which they can explore a virtual world. Each user takes control of a computerized persona (also called character). One can walk around, chat with other characters, explore dangerous areas full of monsters and traps, solve puzzles and quests, and even create your own locations and objects.

There are several families of MUDs, all with their own characteristics. These aspects are usually a matter of playing style (roleplaying, hack'n'slash, ...) But also in the underlying system, various flavours can be found.

The most common MUD types are:

DikuMUD
This is a MUD type which is newer than LPmud, though it lacks some of the flexibility. Object types are hardcoded, and except for a little customization of predefined object templates, users cannot create any new things by themselves.

LPmud
This is certainly the most popular MUD type. Players are usually not allowed to build (until they reach wizard-level) but the game is very flexible, because the gaming world is completely written in a builtin object oriented language called LPC.

TinyMUSH
This s a MUD type derived from TinyMUD (an old type), and it contains a very primitive script-like language which gives limited programming capabilities to users. The acronym MUSH stands for Multi-User Shared Hallucination.

LambdaMOO
MOO stands for MUD Object Oriented. LambdaMOO is a MUD type which is based on the original MOO project but lots of functionality was added and it is more stable. MOO claims to have a C-like internal language but the language is more like functional languages in reality.