Named graphs are an extension of the Resource Description Framework (RDF) data model in which an RDF graph is identified using a Uniform Resource Identifier (URI), thus allowing for the publishing and presentation of metadata about that graph as a whole. The concept behind named graphs is that having multiple RDF graphs in a single repository and naming them with URIs provides useful additional functionality. Named graphs can be represented as the fourth part of a quad, with
<graphname> being the URI of the named graph. This process allows for tracking the provenance and source of the RDF data and supports versioning by providing a way to describe things such as information about the creation and modification of the triples in the named graph. A named graph is sometimes referred to as a quad store.