Discrete event simulation is a method of building computer models to observe the time based behavior of a system. Models are executed in a simulation environment and generate results that provide insight into a system and a basis to make decisions on.

One area where simulation is commonly used is in the area of developing new systems, particularly those that involve a high capital investment. For example, simulation can be used to test the performance of assembly lines to ascertain the throughput possible, the level of utilization of operators and any potential problems. Further simulation can assess the best position for work-in-progress stores and the levels to be used.