About RDF/OWL Vocabulary Concepts

This topic introduces the different concepts you must be familiar with prior to creating a vocabulary.

This page discusses:

See Also
Basic RDF and OWL Elements

RDF

Acronym for Resource Description Framework. It is a language for representing information about resources on Internet. In this language everything (or fact) can be described as a triple (or statement): [Subject, Predicate, Object]. For example, the following statement is a triple where the subject is the Louvre isLocatedIn Paris.

A RDF vocabulary regroups key terms used to describe items in a given domain allowing you to classify and refine the access to data. A term (or element), is either a class or a property.

  • A class describes a group of individuals, like a person or a product.
  • A property describes the relationship linking two classes (owl:ObjectProperty), or a characteristic of a class (owl:DataProperty).

OWL

Acronym for Web Ontology Language. It is a language intended to be used when the information contained in documents needs to be processed by applications, as opposed to situations where the content only needs to be presented to humans. OWL can be used to explicitly represent the meaning of terms in vocabularies and the relationship between those terms. This representation of terms and their interrelations is called an ontology. To know more, refer to the OWL Web Ontology Language Overview on the Internet.

Vocabulary

An ontology is identified through a name and a namespace. The name is a human-readable short-name which is viewed as the prefix of the namespace in the XML terminology.

A vocabulary consists of:

  • local definitions of various RDF/OWL resources like classes, predicates, domains, ranges, or literal objects.
  • Other resources imported from other vocabularies.

For example, the namespace can be http://www.3ds.com/vocabularies/ds6w/ and the prefix can be ds6w.

Class or Predicate

A vocabulary entity. A class or a predicate pertaining to a vocabulary is identified through:

  • A local name (for example Product, Person, who, responsible).
  • A namespace prefix which is the one of the vocabulary it pertains to (for example ds6w). The namespace prefix (name of vocabulary) and the local name separated by semicolon ":", makes the URI of the resource (for example "ds6w:who).


Ontology

See OWL.

Axiom

Noun used to denote statements made in RDF/OWL as opposed to the component triples used in the statements.