FACT or FACTS may refer to:

• Civic Action Front of Chad, a defunct political party in Chad
• Falsely Accused Carers and Teachers, a British support group
• Federation Against Copyright Theft
• Federation of American Consumers and Travelers
• Fertilisers and Chemicals Travancore, a fertiliser and chemical manufacturing company in India
• First Aid Care Team, a former emergency medical unit in the US
• Foundation for Advancement in Cancer Therapy
• Foundation for Art and Creative Technology, a multimedia complex based in Liverpool, England
• First Atheist Church of True Science, founded by Michael Newdow

A fact is something that has really occurred or is actually the case. The usual test for a statement of fact is verifiability—that is, whether it can be demonstrated to correspond to experience. Standard reference works are often used to check facts. Scientific facts are verified by repeatable careful observation or measurement (by experiments or other means).

The Web Ontology Language (OWL) is a family of knowledge representation languages for authoring ontologies. Ontologies are a formal way to describe taxonomies and classification networks, essentially defining the structure of knowledge for various domains: the nouns representing classes of objects and the verbs representing relations between the objects. Ontologies resemble class hierarchies in object-oriented programming but there are several critical differences. Class hierarchies are meant to represent structures used in source code that evolve fairly slowly (typically monthly revisions) whereas ontologies are meant to represent information on the Internet and are expected to be evolving almost constantly. Similarly, ontologies are typically far more flexible as they are meant to represent information on the Internet coming from all sorts of heterogeneous data sources. Class hierarchies on the other hand are meant to be fairly static and rely on far less diverse and more structured sources of data such as corporate databases.