Glossary · IIoT, data and AI
Ontology
Also known as: Domain ontology
German: Ontologie
In information science, an ontology is a formal, explicit specification of the concepts of a domain, their properties and the relationships between them, often including logical rules, so that both people and machines can interpret data consistently. Ontologies are commonly expressed in languages such as RDF Schema and OWL.
- IIoT
In one sentence
An ontology formally specifies a domain's concepts, properties and relationships so that people and machines interpret data consistently.
Example
An ontology defines that a pump is a kind of rotating equipment, has a rated flow with the unit cubic meters per hour and is located in a plant section.
Explained in context
Context cards connect this term with others to answer one question. Also in British English and German.
How it applies
- Engineering: In industry, ontologies connect data from different systems, such as engineering, MES and maintenance, by giving shared meaning to equipment, properties and relations.
- Integration: A Knowledge graph stores instance data structured by an ontology and enables queries across sources.
- Documentation: Documentation standards use ontologies too: iiRDS is defined as an RDF-based vocabulary for classifying technical documentation. Documentation teams should reuse existing ontologies rather than invent parallel terms.
Ontology vs. taxonomy
A Taxonomy arranges concepts in a hierarchy of broader and narrower terms. An ontology adds properties, typed relationships and rules, such as a pump has a rated flow or a motor drives a pump. Every taxonomy can be part of an ontology, but not the other way round.