| GOterm | representation of GO terms |
| OntologyEngineI | DESCRIPTION of Interface |
| Relationship | a relationship for an ontology |
| RelationshipI | DESCRIPTION of Interface |
| RelationshipType | a relationship type for an ontology |
| SimpleGOEngine | a Ontology Engine for GO implementing OntologyEngineI |
| Term | interface for ontology terms |
| TermFactory | Instantiates a new Bio::Ontology::TermI (or derived class) through a factory |
| TermI | interface for ontology terms |