1.1 Main purposesThe purpose of this International Standard is to define a set of basic concepts required to describe formal concept representation systems, especially for health sciences, and to describe representation of concepts and characteristics, for use especially in formal computer based concept representation systems. A main motivation is to make it possible to precisely describe content models described in other International Standards.Informally, the term concepts is often used when what is meant is concept representations . However, this leads to confusion when precise meanings are required. Concepts arise out of human individual and social conc