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Contents 
Chapter 1 Introduction .................................................................................................................................. 4 
1.1 Licensing ............................................................................................................................................. 4 
1.2 Conventions ........................................................................................................................................ 4 
Chapter 2 Requirements and the Protégé User Interface .............................................................................. 6 
Chapter 3 What are OWL Ontologies? ......................................................................................................... 6 
3.1 Components of OWL Ontologies ....................................................................................................... 6 
3.1.1 Individuals........................................................................................................................................ 7 
3.1.2 Properties ......................................................................................................................................... 8 
3.1.3 Classes.............................................................................................................................................. 8 
Chapter 4 Building an OWL Ontology ....................................................................................................... 10 
4.1 Named Classes .................................................................................................................................. 13 
4.2 Using a Reasoner .............................................................................................................................. 15 
4.4 Using Create Class Hierarchy ........................................................................................................... 17 
4.5 Create a PizzaTopping Hierarchy ..................................................................................................... 19 
4.6 OWL Properties ................................................................................................................................ 22 
4.7 Inverse Properties .............................................................................................................................. 23 
4.8 OWL Object Property Characteristics .............................................................................................. 24 
4.8.1 Functional Properties ................................................................................................................. 24 
4.8.2 Inverse Functional Properties ..................................................................................................... 25 
4.8.3 Transitive Properties .................................................................................................................. 25 
4.8.4 Symmetric and Asymmetric Properties ..................................................................................... 25 
4.8.5 Reflexive and Irreflexive Properties .......................................................................................... 26 
4.8.6 Reasoners Automatically Enforce Property Characteristics ...................................................... 26 
4.9 OWL Property Domains and Ranges ................................................................................................ 26 
4.10 Describing and Defining Classes .................................................................................................... 29 
4.10.1 Property restrictions ................................................................................................................. 29 
4.10.2 Existential Restrictions ............................................................................................................ 31