An MMO game, or massively multiplayer online game, is an online video game that allows a large number of players to play on the same server simultaneously. MMOs usually feature a huge, persistent open world, although there are games that differ. These games can be found for most network-capable platforms, including the personal computer, video game console, or smartphones and other mobile devices. MMOs can enable players to cooperate and compete with each other on a large scale, and sometimes to interact meaningfully with people around the world.
MMORPG, or massively multiplayer online role-playing game, is a subgenre of MMOs that combines aspects of a role-playing video game and a massively multiplayer online game. In MMORPGs, the player assumes the role of a character and takes control over many of that characters actions. MMORPGs are distinguished from single-player or small multi-player online RPGs by the number of players able to interact together, and by the games persistent world, which continues to exist and evolve while the player is offline and away from the game.
Most MMORPGs are deployed using a client-server system architecture. The server software generates a persistent instance of the virtual world that runs continuously, and players connect to it via a client software. The client software may provide access to the entire playing world, or further expansions may be required to be purchased to allow access to certain areas of the game.
