# Ontology

### Definition

An ontology is the template for all the actors in your contracts. It defines what [information](https://docs.atfinity.io/guides/glossary/information) should be collected when an instance of that ontology is used in a [case](https://docs.atfinity.io/guides/glossary/case).

### Example

A person is a good example for an ontology. Using the word person does not mean a specific individual. It is a generic term, meaning a human being. The ontology of person is therefore a template to describe an individual person. The template could say that every person should have first name, last name and a date of birth. These things that describe an individual person are information of the ontology.

An ontology can also have different [roles](https://docs.atfinity.io/guides/glossary/role) which other instances can take. An example for an ontology's role could be mother and father which every individual person has. These roles can be taken by other individuals. So a person called Jim Jones could have a mother called Anna Jones and father called Anthony Jones.