The Resource Description Framework (RDF), developed under the sponsorship of the World Wide Web Consortium (W3C), is an infrastructure that enables the encoding, exchange, and reuse of structured metadata.
This infrastructure enables metadata interoperability through the design of mechanisms that support common conventions of semantics, syntax, and structure. RDF does not specify semantics for each resource description community, but rather provides the ability for these communities to define metadata elements as needed. RDF uses XML (eXtensible Markup Language) as a common syntax for the exchange and processing of metadata. The XML syntax is a subset of the international text processing standard SGML (Standard Generalized Markup Language) specifically intended for use on the Web.
The XML syntax provides vendor independence, user extensibility, validation, human readability, and the ability to represent complex structures. By exploiting the features of XML, RDF imposes structure that provides for the unambiguous expression of semantics and, as such, enables consistent encoding, exchange, and machine-processing of standardized metadata.
RDF supports the use of conventions that will facilitate modular interoperability among separate metadata element sets. These conventions include standard mechanisms for representing semantics that are grounded in a simple, yet powerful, data model discussed below. RDF additionally provides a means for publishing both human-readable and machine-processable vocabularies.