Due to the emergence of the semantic Web and the increasing need to formalize
human knowledge, ontologie engineering is now an important activity. But is
this activity very different from other ones like software engineering, for
example ? In this paper, we investigate analogies between ontologies on one
hand, types, objects and data bases on the other one, taking into account the
notion of evolution of an ontology. We represent a unique ontology using
different paradigms, and observe that the distance between these different
concepts is small.