A game in which the players are allowed to communicate and interact prior to the each player's decision as to how to play the game.

a game wherein two or more players do not compete, but rather strive toward a unique objective and therefore win or lose as a group

a structure in which the players have the option of planning as a group in advance of choosing their actions

A game in which joint-action agreements, pre-game contracts, etc., are enforceable.

A cooperative game is a game where groups of players ("coalitions") may enforce cooperative behaviour, hence the game is a competition between coalitions of players, rather than between individual players.