Computer model

simulation, run on a single computer, or a network of computers, to reproduce behavior of a system; modeling a real physical system in a computer

A computer-based predictive model is a computer program that is designed to simulate what might or what did happen in a situation. They are used in many ways including in astronomy, economics and sciences such as physics and biology. Computer models are used in fields such as earthquake performance simulation and making models of buildings.

A NASA supercomputer. Computers like these are often used to run the most complicated computer models

Well known areas which use computer models:

Computer modelling often uses numerical analysis to approximate the real solution of the problem. Simulation techniques are then used to get values. Numerical weather predictions are too inaccurate to give a good local prediction of the weather, so other methods are used to adjust them.