Web resource: Difference between revisions

Revision as of 18:27, 7 October 2007

Revision as of 18:28, 7 October 2007

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The concept of '''Resource''' is primitive in the [[World Wide Web|Web]] architecture, and is used in the definition of its fundamental elements. The term was first introduced to refer to targets of [[Uniform Resource Locator |Uniform Resource Locators]] (URLs), but its definition has been further extended to include the [[referent]] of any [[Uniform Resource Identifier]] (RFC 3986), or [[Internationalized Resource Identifier]] (RFC 3987). In the [[Semantic Web]], abstract resources and their semantic properties are described using the family of languages based on [[Resource Description Framework]] (RDF).

== History ==

--[[User:74.160.68.20|74.160.68.20]] 18:26, 7 October 2007 (UTC)--[[User:74.160.68.20|74.160.68.20]] 18:26, 7 October 2007 (UTC)== History ==

The trefdghhsfhgconcept of resource has evolved during the Web history, from the early notion of static addressable [[document]] or [[file]], to a more generic and abstract definition, now encompassing every ''thing'' or [[entity]] that can be identified, named, addressed or handled, in any way whatsoever, in the Web at large, or in any networked information system. The declarative aspects of a resource ([[identification]] and naming) and its functional aspects (addressing and technical handling) were not clearly distinct in the early specifications of the Web, and the very definition of the concept has been the subject of long and still open debate involving difficult, and often arcane, technical, social, linguistic and philosophical issues.

=== From documents: DOand NOTfiles READto THIS!Web resources ===

In the early specifications of the Web (1990-1994), the term "resource" is barely used at all. The Web is designed as a network of more or less static addressable objects, basically files and documents, linked together in the form of an hypertext. The objects are considered insofar as they can be addressed and handled through a specific protocol, Web documents are accessed and browsed using [[HTTP]] protocol, files are exchanged using [[File transfer protocol|file transfer protocol]], etc.

The first systematic use of the term resource was introduced in June 1994 by RFC 1630. In this document is defined the generic notion of [[Universal Resource Identifier]] (URI), with its two variants [[Uniform Resource Locator |Universal Resource Locator]] (URL) and [[Uniform Resource Name |Universal Resource Name]] (URN). A resource is implicitly defined as something which can be identified, the identification deserving two distinct purposes, naming and addressing, the latter only being dependent on a protocol. It is noticeable that RFC 1630 does not attempt to define at all the notion of resource, actually it barely uses the term besides its occurrence in URI, URL and URN, and still speaks about "Objects of the Network".

RFC 1738 (December 1994) further specifies URLs, the term 'Universal' being changed to 'Uniform'. The document is making a more systematic use of 'resource' to refer to objects which are 'available', or 'can be located and accessed' through the Internet. There again, the term 'resource' itself is not explicitly defined.

===From Web resources to abstract resources===

The first explicit definition of resource is found in RFC 2396, in August 1998 :

''A resource can be anything that has identity. Familiar examples include an electronic document, an image, a service (e.g., "today's weather report for Los Angeles"), and a collection of other resources. Not all resources are network "retrievable"; e.g., human beings, corporations, and bound books in a library can also be considered resources.''

If examples in this document are still limited to physical entities, the definition opens the door to more abstract resources. Providing a concept is given an identity, and this identity is expressed by a well-formed URI, then a concept can be a resource as well.

In January 2005, RFC 3986 makes this extension of the definition completely explicit:

''... abstract concepts can be resources, such as the operators and operands of a mathematical equation, the types of a relationship (e.g., "parent" or "employee"), or numeric values (e.g., zero, one, and infinity).''

== Resources in RDF and the Semantic Web ==