Ontology Components

Individuals, Classes, Attributes, Relations, Etc

Most ontologies use the same basic set of components. The first four are the “main” ones.

• Individuals
  • Instances of a class¹
• Classes (or “kinds”)
  • A kind of thing that can have properties (nouns)
• Attributes
  • Properties that members of a class can have
• Relations
  • How classes or individuals can relate to others
• Restrictions
  • What must be true about something to be valid
• Rules/Axioms
  • Logical statements describing inferences that can be made
• Events
  • Changing of attributes or relations

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Source §

• Ontology components - Wikipedia

Related §

• Ontology
• Ontology, Semantics, and Syntax
• Ontology Language
• Protege

Footnotes §

1. although some research has lead me to think this isn’t well controlled; or perhaps just the usage of “individuals” within an ontology is either open for debate or I’m just not clever enough to wrap my brain around it. One source showed Ford Broncho as an individual of a 4-wheel drive class. It seems likely that there isn’t just one “right” way to do things. That’s not how I would do it, though. ↩