Game (InstanceClass, 6)
From Compile Worlds
A game is a form of entertainment where you try and accomplish some goal.
If there is no goal to accomplish, you are instead talking about a non-game or a toy, as Will Wright likes to cleverly point out to us.
One huge, important category of games are video games.
Multiplayer games are games where multiple people play with or against each other. The latter case is most common and involves conflicting goals so that only one player can win.