Simulation testing involves imitation of the operation of an application or system over time. Simulation testing is used to determine long term outcomes of probability based applications. Simulation is also used for performance optimization, stress testing, strategy testing etc.
Example of simulation testing: A game based on probabilities has a Return To Player or RTP (total win/initial bet ratio) that converges to a specific value after playing a million games. The RTP determines the long term profit from the game. As it is important to know this value accurately, simulators are used to run the game several millions to billions of times in a very short time frame.