An expression of the relationships between a designed artifact, its purpose, the designer's conceptualisation, and the
contextual constrains realising the purpose. The logical reasons given to justify a designed artifact. An explanation why a designed artifact (or some feature of an artifact) is the way it is. Documentation of (a) the reasons for the design of an artifact, (b) the stages or steps of the design process, (c) the history of the design and its context.