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From Library of Congress Subject Headings


Uniform Resource Identifiers


  • URI(s)

  • Instance Of

  • Scheme Membership(s)

  • Collection Membership(s)

  • Variants

    • us: Identifiers, Uniform Resource
    • us: Resource Identifiers, Uniform
    • us: URIs (Uniform Resource Identifiers)
  • Related Terms

  • Sources

    • found: Work cat.: Association for Library Collections & Technical Services. Task Force on Uniform Resource Identifiers and AACR2. Report, 2002: p. 4 ("A Uniform Resource Identifier (URI) is a compact character string that refers to an electronic resource. A URI provides a simple and extensible means for identifying a resource that can then be used within applications. The IETF has proposed a generic syntax to which all URIs must conform. URIs form a superset of three distinct classes of identifiers: Uniform Resource Locators (URLs), Uniform Resource Names (URNs), and Uniform Resource Characteristics (URCs). Since the URI standard was originally proposed, work on defining URCs has been abandoned.")
    • found: World Wide Web Consortium (W3C) home page, May 15, 2002: URI/URL ("Uniform Resource Identifiers (URIs, aka URLs) are short strings that identify resources in the web: documents, images, downloadable files, services, electronic mailboxes, and other resources. They make resources available under a variety of naming schemes and access methods such as HTTP, FTP, and Internet mail addressable in the same simple way."; URI: Uniform Resource Identifier - The generic set of all names/addresses that are short strings that refer to resources; URL: Uniform Resource Locator - An informal term (no longer used in technical specifications) associated with popular URI schemes: http, ftp, mailto, etc.; URN: Uniform Resource Name - 1. An URI that has an institutional commitment to persistence, availability, etc. Note that this sort of URI may also be a URL. See, for example, PURLs.)
    • found: Berners-Lee, T. Uniform Resource Identifiers (URI): generic syntax, via WWW, May 15, 2002 ("A Uniform Resource Identifier (URI) is a compact string of characters for identifying an abstract or physical resource ... This specification of URI syntax and semantics is derived from concepts introduced by the World Wide Web global information initiative, whose use of such objects dates from 1990 and is described in 'Universal Resource Identifiers in WWW' [RFC1630] ... A URI can be further classified as a locator, a name, or both. The term 'Uniform Resource Locator' (URL) refers to the subset of URI that identify resources via a representation of their primary access mechanism (e.g., their network 'location'), rather than identifying the resource by name or by some other attribute(s) of that resource. The term 'Uniform Resource Name' (URN) refers to the subset of URI that are required to remain globally unique and persistent even when the resource ceases to exist or becomes unavailable.")
  • Change Notes

    • 2002-10-29: new
    • 2013-09-27: revised
  • Alternate Formats

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