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RDF Triple

An RDF Triple is a three-tuple record of URI References (in the RDF standard) that define a subject, a predicate and an object.

  • Context:
  • Example(s):
    • <rdf:Description rdf:about="#HarryPotter"> <hasPet rdf:resoruce="#Hedwig"/><hasEmail></hasEmail></rdf:Description>, where #HarryPotter and #Hedwig are fragment identifiers.
  • Counter-Example(s):
  • See: RDF Vocabulary, RDF.




    • The underlying structure of any expression in RDF is a collection of triples, each consisting of a subject, a predicate and an object. A set of such triples is called an RDF graph (defined more formally in section 6). This can be illustrated by a node and directed-arc diagram, in which each triple is represented as a node-arc-node link (hence the term "graph").

      Each triple represents a statement of a relationship between the things denoted by the nodes that it links. Each triple has three parts: a subject, an object, and a predicate (also called a property) that denotes a relationship.

      The direction of the arc is significant: it always points toward the object.

      The nodes of an RDF graph are its subjects and objects.

      The assertion of an RDF triple says that some relationship, indicated by the predicate, holds between the things denoted by subject and object of the triple. The assertion of an RDF graph amounts to asserting all the triples in it, so the meaning of an RDF graph is the conjunction (logical AND) of the statements corresponding to all the triples it contains. A formal account of the meaning of RDF graphs is given in [RDF-SEMANTICS].