As every artifact, models can be defined by nature and function. With regard to nature, models are symbolic representations, descriptive (categories of actual instances) or prescriptive (blueprints of artifacts). With regard to function, models can be likened to currency, as they serve as means of exchange, instruments of measure, or repository.
Along that understanding, models can be neatly characterized by their intent:
- No use of models, direct exchange (barter) can be achieved between business analysts and software engineers.
- Models are needed as medium supporting exchange between organizational units with different business or technical concerns.
- Models are used to assess contents with regard to size, complexity, quality, …
- Models are kept and maintained for subsequent use or reuse.
Depending on organizations, providers and customers could then be identified, as well as modeling languages.