The OWL Standard and Ontology Modelling

In recent years, there has been an uptake of expressing ontologies using ontology languages such as the Web Ontology Language (OWL). OWL is a semantic web computational logic-based language, designed to represent rich and complex knowledge about things and the relations between them. It also provides detailed, consistent and meaningful distinctions between classes, properties and relationships.

By specifying both object classes and relationship properties as well as their hierarchical order, OWL enriches ontology modeling in semantic graph databases, also known as RDF triplestores. OWL, used together with an OWL reasoner in such triplestores, enables consistency checks (to find any logical inconsistencies) and ensures satisfiability checks (to find whether there are classes that cannot have instances).

Also, OWL comes equipped with means for defining equivalence and difference between instances, classes and properties. These relationships help users match concepts even if various data sources describe these concepts somewhat differently. They also ensure the disambiguation between different instances that share the same names or descriptions.