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IETF Tags for Identifying Languages

Date added 10 August 2009
Last edited 12 November 2009

Full Title

IETF Tags for Identifying Languages


IETF Tags for Identifying Languages describes the structure, content, construction, and semantics of language tags for identifying the language used in an information object. It describes how to register language tag values and how to create extensions.

Standards Developing Organisation



No information

Lifecycle Actions

Access, Use and Reuse
Description and Representation Information

Standard Framework

Digital Archive Standards

Standard Type

Metadata Content Standards

Current Version

Further Information

Alternative Current Versions


Previous Versions

Referenced Standards

Extensible Markup Language (XML) 1.0: 2004
IETF RFC 2026: October 1996, The Internet Standards Process - Revision 3
IETF RFC 1766: March 1995, Tags for the Identification of Languages
IETF RFC 2028: October 1996, The Organizations Involved in the IETF Standards Process
IETF RFC 2047: November 1996, MIME (Multipurpose Internet Mail Extensions) Part Three: Message Header Extensions for Non-ASCII Text
IETF RFC 2119: March 1997, Key words for use in RFCs to Indicate Requirement Levels
IETF RFC 2231: November 1997, MIME Parameter Value and Encoded Word Extensions: Character Sets, Languages, and Continuations
IETF RFC 2434: October 1998, Guidelines for Writing an IANA Considerations Section in IETF RFCs
IETF RFC 2781: February 2000, UTF-16, an encoding of ISO 10646
IETF RFC 2860: June 2000, Memorandum of Understanding Concerning the Technical Work of the Internet Assigned Numbers Authority
IETF RFC 3066: January 2001, Tags for the Identification of Languages
IETF RFC 3339: July 2002, Date and Time on the Internet: Timestamps
IETF RFC 3552: July 2003, Guidelines for Writing IETF RFC Text on Security Considerations
IETF RFC 4234: October 2005, Augmented BNF for Syntax Specifications: ABNF
IETF RFC 4645: September 2006, Initial Language Subtag Registry
IETF RFC 4647: September 2006, Matching of Language Tags