World-Wide Web, specification, data (RDF) A specification
being developed in 2000 by the
W3C as a foundation for
Resource Description Framework data consists of resources
(
nodes), and property/value pairs describing the resource.
A node is any object which can be pointed to by a
URI,
properties are attributes of the node, and values can be
either atomic values for the attribute, or other nodes. For
example, information about a particular
web page (a node),
might include the property "Author". The value for the Author
property could be either a string giving the name of the
author, or a
link to a resource describing the author.
Resource Description Framework only specifies a mechanism for
encoding and transferring meta-data. It does not specify what
that meta-data should, or can be. RDF does not, for example,
define an "Author" attribute. Sets of properties are defined
within RDF Vocabularies (or Schemas). Anynone can create an
RDF schema, describing a specialized set of properties, by
creating a resource, referenced by the Schema URI, which
provides a human- and machine-understandable definition of the
schema's properties. The description of a node may include
properties defined in different schemas. The properties
within a resource description are associated with a certain
Schemas currently being developed include a content screening
system modeled after
PICS, and a bibliographic vocabulary,
(2000-03-25)