21st Century Learning and Teaching

Ontology (introduced ca. 1606) is the philosophical study of the nature of being, becoming, existence, or reality, as well as the basic categories of being and their relations.[1] Traditionally listed as a part of the major branch of philosophy known as metaphysics, ontology often deals with questions concerning what entities exist or may be said to exist and how such entities may be grouped, related within a hierarchy, and subdivided according to similarities and differences. A very simple definition of ontology is that it is the examination of what is meant, in context, by the word 'thing'.[citation needed]

In modern terms, the formal study of reality itself is in the domain of the physical sciences, while the study of personal "reality" is left to psychology. The idea of ontology comes from a time before people could make these distinctions and yet were beginning to investigate the bigger questions ("first things") within the emerging context of secular thought, without religious forms and ideas.