The first step to simulate any system is to build a model from which we can obtain predictions concerning the behavior of the system under study.
A model is an abstraction of some real system that can be used to obtain predictions and formulate control strategies. In particular, models are used to analyze one or more changes in various aspects of a system that may affect other aspects of the same system.
To be useful, a model must necessarily incorporate elements of two conflicting attributes: realism and simplicity.
Realism: The model should serve as a reasonable approximation to the real system and incorporate most of the important aspects of the system.
Simplicity: The model must not be overly complex so as to preclude its understanding and manipulation.
All we require from a model is a high correlation between model predictions and real-life system performance.
Key Features and Components of a Model