Basic Concepts and Vocabulary

This guide uses both technical jargon (of which some is commonly used in the formal ontology field, and some is fairly specific to OBO-Edit) and vocabulary that is more intuitive to biologists. Technical terms and their synonyms may be used in a single sentence.

• Classes/Terms - Classes (often called terms) are the concepts described by your ontology. See An Introduction to OBO Ontologies for a detailed discussion of exactly what classes are. For now, realize that they're probably the part of your ontology that you really care about. They are the entities that you want to classify or processes you want to relate to one another. Anatomical structures and biological processes are examples.
• Relations/Relationship types - Relations (often called relationship types in this guide) describe the relationships between terms. is_a and part_of are both types of relations. See An Introduction to OBO Ontologies for a more detailed discussion.
• Links/Relationships - When two terms have a relationship to one another, that relationship is called a "relationship" (surprise!). A relationship in OBO-Edit consists of a child term, a relationship type, and a parent term. Relationships are directional: the child term has a relationship of the given type to the parent term. Because a relationship indicates a directional connection between two terms, they are sometimes called "links" in this document.