There is a difference between a taxonomy, a conceptual model, and a logical theory. This is explained well in The Ontology Spectium by Dr. Leo Obrst. These differences are shown in this presentation by Deborah L. McGuinness, Ontologies for the Modern Age, Slide 4. I took that information and created my own graphic:
(Click image for larger view)
The graphic shows all the pieces that are necessary to control the description of, verification of, and consumption of information.
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