Easy. The OpenCyc ontology includes all the simple terms (Cyc constants) and composed terms (Cyc non-atomic reified terms) that full Cyc does. OpenCyc includes that subset of of full Cyc assertions which match the definitional statement types of OWL (the web ontology language). E.g. the class cyc:Action is a sub class of cyc:Event which is a sub class of owl:Thing. What is left out of OpenCyc, but included in ResearchCyc (full Cyc) are the ordinary assertions that relate concepts, e.g. cyc:DougLenat cyc:president cyc:Cycorp.
OpenCyc's purpose is to spread the use of the Cyc ontology in the Semantic web and Linked Data.
OpenCyc's purpose is to spread the use of the Cyc ontology in the Semantic web and Linked Data.