This is a one-hour video recording of the presentation of Sean Bechhofer at the KnowledgeWeb summer school 2006. It comprises either the video synchronized with the slides (requires Flash) or the video alone.

Table of Contents: OWL: An Ontology Language for the Web The Semantic Web Vision What is the Problem? A Semantic Web - First Steps Technologies for the Semantic Web Building a Semantic Web Object Oriented Models Structure of an Ontology Ontology Languages Why Semantics? Formal Languages RDF The RDF Data Model Linking Statements RDF Syntax What does RDF give us? RDF(S): RDF Schema RDF(S) Examples RDF/RDF(S) 'Liberality' RDF/RDF(S) Semantics RDF(S) Inference What does RDF(S) give us? Problems with RDF(S) Solution The OWL Family Tree A Brief History of OWL Aside: Description Logics DL Architecture A Brief History of DLs DL Semantics OWL Layering OWL Full OWL DL OWL Lite OWL Syntaxes OWL Class Constructors OWL Axioms OWL Individual Axioms OWL Property Axioms Semantics Reasoning Instance Reasoning Why Reasoning? Example Necessary and Sufficient Conditions Example Common Misconceptions Disjointness Domain and Range And/Or and Quantification Closed and Open Worlds Extensions Rules Extensions: SWRL Rules: SWRL Extensions: Query and Retrieval Extensions: Query Languages Query Languages Extensions: Datatyping Extensions: Modularity Extensions: OWL 1.1 Tools Summary Acknowledgements Thank you!