Module Models and Modelling: 10.2: Categories of models and the model-being

Often models are not developed from scratch (as greenfield development) or by layman without previous experience. Models have often predecessors, are often based on origins that are already models, have a journey of model-being and none-being, and are refined to more specific ones. We thus need a treatment of models that allows to tune the level of abstraction, the scope of consideration, and the focus of attention. Our approach is based on an integrated treatment of the triple (stereotype, pattern, template) that is the hidden background of model-driven development (see Chapter 14). It allows to develop canonic categories and stepwise refinement to the most appropriate model. Finally, we propose a decision framework for the question whether an artefact or object or thought is a model.