Abstract
Ontologies have gained popularity in a wide range of research fields, in the domains where possible interpretations of terms have to be narrowed and there is a need for explicit inter-relations of concepts. Although reusability has always been claimed as one of the main characteristics of ontologies, it has been shown that reusing domain ontologies is not a common practice. Perhaps this is due to the fact that despite a large number of works towards complexity management of ontologies, popular systems do not incorporate enough functionality for ontology explanation. We analyse the state of the art and substantiate a minimal functionality that the system should provide in order to make domain ontologies better understandable for their users.