Taxonomy
A taxonomy identifies hierarchical relationships among concepts within a domain. A taxonomy categorizes items within a single dimension: high-level categories are broken down into sub-categories, and then into further sub-categories in a branching but linear fashion, all the way down to an individual entity. A taxonomy does not represent relationships across categories, only hierarchically.
| Ontology | Taxonomy | Thesaurus | Vocabulary | |
|---|---|---|---|---|
| Describes | Concepts (content) and the relationships between them (structure), including axioms and restrictions | Hierarchical relationships among concepts, and specifies the term to be used to refer to each | Hierarchical and non-hierarchical relationships among concepts | General term for a collection of concepts (words) to do with a domain |
| Relationships | Typed hierarchical and associative | Basically hierarchical, but all modeled using same notation | Untyped hierarchical, associative, and equivalence | Unspecified (abstract concept) |
| Properties | RDFS defines relationship properties and restrictions | None | Can be described in scope notes if required | Unspecified (abstract concept) |
| Structured | Network | Tree | Cross-branch tree | Unspecified (abstract concept) |