Effective Modeling
All models have a purpose and an effective model contains only the details needed to fulfill its purpose. for example, you won’t see subway stops on a world map. On the other hand, you cannot use a subway map to estimate distances. Each map contains just the information it is supposed to provide.
In its essence, a model is an abstraction the notion of abstraction allows us to handle complexity by omitting unnecessary details and leaving only what is needed to solve the problem at hand