Topic Relation

How can a web page or document be associated with a resource?


There is often a need to associate a resource with a page or document that provides further, human-readable content about the resource. This information may often be present in a content management system or dataset as "further reading" links. How can these relations be published as RDF, clearly identifying the relationship between the document and the resource being described?


Use the foaf:topic and/or foaf:primaryTopic relationships to associate a resource with a page(s) in which it is featured or discussed


In a dataset describing Paris, some additional further reading links may be available:

<> a ex:Place;
   skos:prefLabel "Paris"@fr.

   foaf:primaryTopic <>.

   foaf:topic <>.


There will always be a mix of unstructured documents and structured data on the Semantic Web. There are many kinds of relations that could be expressed between a document and a resource, but a very common relation is one of categorisation, e.g. identifying when a document or page has a specific focus or theme. The FOAF topic terms, foaf:topic and foaf:primaryTopic provide a means to link a document directly with a resource which features as a topic in that document.

Other vocabularies provide similar related properties that may be more useful in some scenarios. For example Dublin Core defines the dc:subject property, but this is best used to relate a document to an entry in a controlled vocabulary, e.g. a subject heading, rather than a "real world" resource.

Because the Topic Relation pattern involves making statements about other resources on the web, it is an application of the Annotation pattern.