RDF Terminology and Concepts
- 12 January 2001
- Graham Klyne
- Graham Klyne
- Brian McBride
- Bill dehOra
- Dan Brickley
This is currently a live working document, being a collection of suggestions
from participants in the W3C RDF Interest Group.
- RDFM&S, M&S:
- The RDF Model and Syntax Specification.
- Data describing Web resources [RDFM&S].
- Web Resource:
- Anything that is identified by a URI [RFC2396].
- Anything which exists or has existed. Note that RFC2396 uses this term in
a more restricted sense, to mean some data represents some aspect of a Web
- RDF Resource:
- [See RDF M&S section 5] Note that an RDF resource is not necessarily a web
resource, though any web resource can be an RDF resource.
- Consider: http://foo.com/#a and http://foo.com/#b may name distinct RDF
resources, but if used to access web resources they both refer to the common
web resource http://foo.com/
- [[[This distinction between "Web resource" and "RDF Resource"
is not a desired outcome, but an interpretation of different uses of the term
"resource" in different documents.]]]
- May refer to an RDF resource or a Web Resource. Some resources may be both.
In discussion of RDF, this term is often used to mean RDF Resource.
- RDF Resource Identifier, Resource Identifier:
- A URI plus optional anchor ID.[RDFM&S]
- RDF Resource Identifiers are understood to name RDF Resources.
- RDF Statement, Statement:
- [See RDFM&S section 5]
- RDF Description:
- [See RDFM&S] Construct containing representations of a number of RDF statements
about a specific RDF resource, and possibly some additional statements.
- The entity or concept that an RDF Resource describes. [RDFM&S]
- Distributive Referent:
- A Referent that describes each of the Resources in a container, not including
the container. The Referent is said to be made on the container. [RDFM&S]
- Description [of]:
- (As opposed to RDF Description) Language or data structure providing information
about some entity or concept.
- Stand for:
- The use of one entity or concept in a description to refer to some other
entity or concept. For example, "X stands for Y in Z" meaning that
occurrences of "X" in "Z" are to be understood as references
- Reification (of a statement):
- [See RDFM&S section 5] A resource that stands for the statement together
with the four statements that describe the statement. More than one reification
may exist for a given statement.
- (There is some debate whether multiple reifications of a statement are
- Reified Statement:
- [See RDFM&S section 5] A resource that stands for a statement in a Reification.
This resource has four properties describing the statement, and maybe others.
- Reification Quad:
- The four statements that make up a Reification.
- A data structure (abstract or concrete) that captures some essential properties
of some entity or concept.
- Representing [x]:
- Being a representation of [x] (see above)
- An environment within which some statements are taken to be true.
- A reference to a statement without necessarily making any assertion about
its truth or falsity.
- The expression of an RDF statement [or set of statements] in some context
of discourse that is taken to be an assertion of the truth of the statement[s]
in that context.
- [See RDFM&S section 5].
- This term is used in three distinct ways:
- (a) The RDF Model, meaning the underlying structure and interpretation of
- (b) An RDF Model, meaning a collection of RDF statements
- (c) Logical Model, being a formal logicians term with quite specific meaning.
- (This term has caused some confusion, since it has a quite specific meaning
to logicians, which is not the same as some would regard as its "natural"
- RDF Graph:
- A set of RDF Statements.
- Reification of an RDF Graph:
- A (bag/collection?) containing the reifications of the statements
in an RDF Graph
- Reified Graph:
- The (bag/collection?) in the reification of an RDF graph.
- Higher Order Statement:
- A Statement whose Referent is another Statement.[RDFM&S]
- Higher Order Context:
- A Context whose Referent is another Context.
Some related resources / context:
W3C site index / technology keywords
Glossary from 'Weaving the Web'.
http://www.w3.org/WCA/ Web Characterisation
Initiative (historical interest)
Web Characterization Terminology & Definitions Sheet W3C Working Draft 24-May-1999
HTTP-NG Activity Statement (historical interest)
HTTP-NG Web Interfaces (an attempt to formalise our a notion of URIs, resources
etc in terms of a distributed object type hierarchy).
and Addressing: URIs, URLs, ...
-- for HTTP 1.1's notion of URI, 'resource', entity etc...
Insightful comments were provided by Pierre-Antoine Champin.