Early Computer Simulation

Computer simulation developed hand-in-hand with the rapid growth of the computer, following its first large-scale deployment during the Manhattan Project in World War II to model the process of nuclear detonation (nuclear weapon) - wikipedia

Computer simulation is often used as an adjunct to, or substitute for, modeling systems for which simple closed form analytic solutions (closed-form solution) are not possible.

There are many types of computer simulations; their common feature is the attempt to generate a sample of representative scenarios for a model in which a complete enumeration of all possible states of the model would be prohibitive or impossible.