description of the concepts and relationships that can formally exist for an agent or a community of agents.
An ontology is an unambiguous analysis of all the entities, their properties, the relations between them, and functions within a given domain. What can exist. What things can happen. How can do those things all interact and relate to one another. Written ontologies are knowledge encapsulated and encoded for use in the future, use by others, and/or for having a basis upon which re-engineering efforts can be made.
An ontology is where the real world meets the code that is being written to perform functions within it. Models of systems are representations of (usually sections of) that systems ontology.
No matter what discipline or domain is being described, most ontologies use the same Ontology Components. Describing an ontology takes some variety of Ontology Language (e.g. IDEF5), and a software in which to do the work. Semantic Wikis are a form of Ontology Software.
The internet is a partial ontology, through the use of semantic links and things like the JSON-LD syntax for RDF.
Source
- Wikipedia
- Ontology (information science) - Wikipedia
- IDEF5 - Ontology Description Capture Method - IDEF