A simulation is an experience modeled on real life activities. Simulation games are usually non-combative, and focus on ordinary experiences, like growing and harvesting food, or building cities. You can think of a simulation game as a hybrid of roleplay and mundane resource management. SimAnt – The Electronic Ant Colony, first published in 1991, is an example of an early simulation game, where the player controlled a nest of ants.
Simulator and simulation are often used interchangeably. Also see simulator.