2.2 Models, Views, and Diagrams

2.2.1 What is a Model?

Models are often built in the context of business and IT systems in order to better understand existing or future systems. However, a model never fully corresponds to reality. Modeling always means emphasizing and omitting: emphasizing essential details and omitting irrelevant ones. But what is essential and what is irrelevant? There is no universal answer to this question. Rather, the answer depends on what the goals of the model are and who is viewing or reading it.


Think about what is emphasized or omitted in the following models:

  • A wind tunnel model of a car
  • A model of a building scaled at 1:50
  • A route plan of the subway
  • A map
  • An organization chart

The more information a model is supposed ...

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