In online gaming, a MUD (multi-user dungeon), pronounced /m^d/, is a multi-user real-time virtual world described entirely in text. It combines elements of role-playing games, hack and slash, interactive fiction, and online chat. Players can read descriptions of rooms, objects, other players, non-player characters, and actions performed in the virtual world. Players interact with each other and the world by typing commands that resemble a natural language.
Traditional MUDs implement a fantasy world populated by fictional races and monsters, with players being able to choose from a number of classes in order to gain specific skills or powers. The object of this sort of game is to slay monsters, explore a fantasy world, complete quests, go on adventures, create a story by roleplaying, and advance the created character. Many MUDs were fashioned around the dice rolling rules of the Dungeons & Dragons series of games.
Such fantasy settings for MUDs are common, while many others are set in a science fiction.based universe or themed on popular books, movies, animations, history, and so on. Not all MUDs are games; some, more typically those referred to as MOOs, are used in distance education or for virtual conferences. MUDs have attracted the interest of academic scholars from many fields, including communications, sociology, law, and synthetic economies.
Most MUDs are run as hobbies and are free to players; some may accept donations or allow players to purchase virtual items, while others charge a monthly subscription fee. MUDs can be accessed via standard telnet clients, or specialized MUD clients which are designed to improve the user experience. Numerous games are listed at various web portals, like The Mud Connector.
It has been argued that modern games like World of Warcraft, and social virtual worlds such as Second Life can have their origins traced back to the early MUDs. Originally graphical virtual worlds were called graphical MUDs, most notably Everquest, but by 2000 the term MMORPG (massively multiplayer online role-playing game) had become the standard. The MMORPG RuneScape started out as a text-based MUD before graphics were added. Many MUDs are still active and a number of influential MMORPG designers, such as Raph Koster, Brad McQuaid, Mark Jacobs, Brian Green, and J. Todd Coleman, began as MUD developers and/or players.