[FOAF](https://xmlns.com/foaf/spec/) (Friend of a Friend) is one of the earliest and most widely used [[ontology|ontologies]] for describing people, their relationships, and social networks. It was created by Dan Brickley and Libby Miller in the early 2000s, written in [[RDF]] and [[OWL]], and designed to help systems interoperate and share data about people across the web. |FOAF Term|Description| |---|---| |`foaf:Person`|A class representing a person| |`foaf:name`|The person's full name| |`foaf:givenName`|First name| |`foaf:familyName`|Last name / surname| |`foaf:mbox`|The person's email (as a `mailto:` URI)| |`foaf:homepage`|URL of the person’s homepage| |`foaf:knows`|Relationship to another person| |`foaf:img`|A depiction (usually a photo)| |`foaf:account`|A reference to an online account (e.g., social media)| |`foaf:organization`|(Used indirectly via properties like `foaf:member`)| You can combine FOAF and [[schema.org]] when building RDF knowledge graphs. For instance, use `foaf:knows` to model a friendship and `schema:Person` for richer profile data.