model

Simplified version of some aspect of the real world. Models are produced to show the relationships between two or more factors, such as land use and the distance from the centre of a town (for example, concentric-ring theory). Because models are idealized, they give only a general guide to what may happen.

model

In computing, set of assumptions and criteria based on actual phenomena, used to conduct a computer simulation. Models are used to predict the behaviour of a system such as the movement of a hurricane or the flow of goods from a store. In industry, they are important tools for testing new products: engineers subject virtual prototypes of aircraft or bridges to various scenarios to find out what adjustments are necessary to the design. However, a model is only as good as the assumptions that underlie it.

Models may run at the same speed of the real situation (real-time models) or run at faster or slower speeds.

Models are also the basis for expert systems, which simulate the knowledge of a human expert.