See more Identifier articles on AOD.

Powered by
Share this page on
Article provided by Wikipedia

Main article: "Unique identifier

Many resources may carry multiple identifiers. Typical examples are:

The inverse is also possible, where multiple resources are represented with the same identifier (discussed below).

Implicit context and namespace conflicts[edit]

Naming collision

Many "codes and "nomenclatural systems originate within a small "namespace. Over the years, some of them bleed into larger namespaces (as people interact in ways they formerly hadn't, e.g., cross-border trade, scientific collaboration, military alliance, and general cultural interconnection or assimilation). When such dissemination happens, the limitations of the original naming convention, which had formerly been latent and moot, become painfully apparent, often necessitating "retronymy, "synonymity, translation/"transcoding, and so on. Such limitations generally accompany the shift away from the original context to the broader one. Typically the system shows implicit context (context was formerly assumed, and narrow), lack of capacity (e.g., low number of possible IDs, reflecting the outmoded narrow context), lack of "extensibility (no features defined and reserved against future needs), and lack of specificity and disambiguating capability (related to the context shift, where longstanding uniqueness encounters novel nonuniqueness). Within computer science, this problem is called "naming collision. The story of the origination and expansion of the "CODEN system provides a good case example in a recent-decades, technical-nomenclature context. The capitalization variations seen with "specific designators reveals an instance of this problem occurring in "natural languages, where the proper noun/common noun distinction (and its complications) must be dealt with. A universe in which every object had a UID would not need any namespaces, which is to say that it would constitute one gigantic namespace; but human minds could never keep track of, or semantically interrelate, so many UIDs.

Identifiers in various disciplines[edit]

Identifier Scope
"atomic number, corresponding one-to-one with "element name international (via "ISV)
"Australian Business Number Australian
"CAGE code U.S. and "NATO
"CAS registry number originated in U.S.; today international (via "ISV)
"CODEN originated in U.S.; today international
"Digital object identifier (DOI, doi) "Handle System "Namespace, international scope
"DIN standard number originated in Germany; today international
"E number originated in E.U.; may be seen internationally
"EC number
"Employer Identification Number (EIN) U.S.
"Global Trade Item Number international
"Group identifier many scopes, e.g., specific computer systems
"International Chemical Identifier international
"International Standard Book Number (ISBN) ISBN is part of the "EAN "Namespace; international scope
International eBook Identifier Number (IEIN) international
"International Standard Serial Number (ISSN) international
"ISO standard number, e.g., "ISO 8601 international
"Library of Congress Control Number U.S., with some international bibliographic usefulness
"Personal identification number many scopes, e.g., banks, governments
"Personal identification number (Denmark) Denmark
"Pharmaceutical code Many different systems
Product batch number
"Serial Item and Contribution Identifier U.S., with some international bibliographic usefulness
"Serial number many scopes, e.g., company-specific, government-specific
Service batch number
"Social Security Number U.S.
"Tax file number Australian

See also[edit]


  1. ^ Malik, D. (2014). C++ programming : from problem analysis to program design (7th edition. ed.). Cenage Learning. p. 397. "ISBN "978-1-285-85274-4. 
  2. ^ "The Go Programming Language Specification - The Go Programming Language". 2013-05-08. Retrieved 2013-06-05. 
  3. ^ "University of Glasgow. "Procedure for Applying Identifiers to Documents". Retrieved 28 April 2009. 
  4. ^ "University of Pennsylvania. "Information on Chemical Nomenclature". Retrieved 28 April 2009. 
) )