Game master

A gamemaster (GM; also known as game master, game manager, game moderator or referee) is a person who acts as an organizer, officiant for questions regarding rules, arbitrator, and moderator for a multiplayer role-playing game. They are more common in co-operative games in which players work together than in competitive games in which players oppose each other. The act performed by a gamemaster is sometimes referred to as "Gamemastering" or simply "GM-ing".

The role of a gamemaster in a traditional table-top role-playing game (pencil-and-paper role-playing game) is to weave the other participants' player-character stories together, control the non-player aspects of the game, create environments in which the players can interact, and solve any player disputes. The basic role of the gamemaster is the same in almost all traditional role-playing games, although differing rule sets make the specific duties of the gamemaster unique to that system.

The role of a gamemaster in an online game is to enforce the game's rules and provide general customer service. Also, unlike gamemasters in traditional role-playing games, gamemasters for online games in some cases are paid employees.

The term gamemaster and the role associated with it could be found in the postal gaming hobby. In typical play-by-mail games, players control armies or civilizations and mail their chosen actions to the GM. The GM then mails the updated game state to all players on a regular basis. Usage in a wargaming context includes Guidon Games 1973 ruleset, Ironclad.

In a role-playing game context, it was first used by Dave Arneson while developing his game Blackmoor in 1971, although the first usage in print may have been Chivalry & Sorcery.

Each gaming system has its own name for the role of the gamemaster, such as "judge", "narrator", "referee", "director", or "storyteller", and these terms not only describe the role of the gamemaster in general but also help define how the game is intended to be run. For example, the Storyteller System used in White Wolf Game Studio's storytelling games calls its GM the "storyteller", while the rules- and setting-focused Marvel Super Heroes role-playing game calls its GM the "judge". The cartoon inspired role-playing game Toon calls its GM the "animator". A few games apply system- or setting-specific flavorful names to the GM, such as the Keeper of Arcane Lore (in Call of Cthulhu); the Hollyhock God (Nobilis, in which the hollyhock represents vanity), or the most famous of such terms, "Dungeon Master" (or "DM") in Dungeons & Dragons.

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Wikipedia