massively multiplayer online game

Massively multiplayer online game (also called MMOG or simply MMO) is a computer game which is capable of supporting hundreds or thousands of players simultaneously. By necessity, they are played on the Internet, and feature at least one persistent world. Some argue that small player-count games, with 200 and fewer players, are also part of the genre; the persistent world is probably the only "hard" requirement.
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Massively multiplayer online role-playing game (MMORPG) is a genre of online computer role-playing games (CRPGs) in which a large number of players interact with one another in a virtual world.As in all RPGs, players assume the role of a fictional character (most commonly in a fantasy world) and take control over many of that character's actions, although, unlike traditional tabletop RPGs such as Dungeons & Dragons, there is a greater focus on progression and social interaction than actual roleplaying. MMORPGs are distinguished from single-player or small multi-player RPGs by the number of players, and by the game's persistent world, usually hosted by the game's publisher, which continues to exist and evolve while the player is away from the game. MMORPGs should also be distinguished from their text-based relatives, sometimes called MU*s (more specifically MUDs, MUSHes, MOOs etc. depending on the codebase, which are generally free games based on an open source codebase.
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