A Massively Multiplayer Online Game (MMOG or MMO) is a computer game which is capable of supporting hundreds or thousands of players simultaneously, and is played on the Internet. Typically, this type of game is played in a giant persistent world. The term MMORPG is sometimes used, which means Massively Multiplayer Online Role-Playing Game.
MMOs enable players to compete with and against each other on a grand scale, and sometimes to interact meaningfully with people around the world. The friendships made on MMOs are sometimes as real as those in the real world, and generate a large amount of online 'social capital'. However, most MMOs require players to invest large amounts of their time into the game (drawing one away from the real world), and are most suitable for the more serious gamer. Still, almost anyone who enjoys video games or human interaction can enjoy an MMOG.