Web Ontology Language

OWL er et akronym for Web Ontology Language, et opmærkningsprog til publicering og deling af data ved hjælp af ontologies på internettet. OWL er en vokabular ekstension af RDF (the Resource Description Framework) og er afledt fra webontologisproget DAML+OIL. Sammen med RDF og andre komponenter udgør disse værktøjer projektet semantisk web.

OWL har for tiden tre versioner: OWL Lite, OWL DL samt OWL Full. Disse tre versioner inkorporer forskellige træk, og i det hele taget er det lettere at ræsonnere om OWL Lite end OWL DL og lettere om OWL DL end OWL Full. OWL Lite og OWL DL These flavors incorporate different features, and in general it is easier to reason about OWL Lite than OWL DL and OWL DL than OWL Full. OWL Lite and OWL DL are constructed in such a way that every statement can be decided in finite time, OWL Full can contain endless 'loops'.

OWL DL is based on the description logic ${\mathcal {SHOIN}}(D)$. Its subset OWL Lite is based on the less expressive logic ${\mathcal {SHIF}}(D)$.

About the acronym

Some may claim that the correct acronym for Web Ontology Language should be WOL instead of OWL. Others believe that the order was chosen in honor of the character Owl from Winnie the Pooh, who wrote his name WOL instead of OWL. In truth, OWL was proposed as acronym that would be easily pronounced, yield good logos, suggest wisdom and honor Bill Martin's One World Language KR project from the 1970s. And, quoting Guus Schreiber: “Why not be inconsistent in at least one aspect of a language which is all about consistency”

See also

• Common Logic (CL)
• RDF
• FOAF + DOAC
• Semantic Web
• Meta-Object Facility (MOF) a different standard for the Unified Modeling Language (UML) of the Object Management Group (OMG)

External links

• OWL Web Ontology Language Overview
• OWL Web Ontology Language Guide
• OWL Web Ontology Language Reference
• What is ontology?
• RacerPro the commercial OWL RDF Reasoner
• KAON2 Inference engine for OWL-DL and DL-safe rules
• OWL Book Book that describes OWL syntax
• Protege OWL OWL plugin for the Protégé ontology editor