Language tags

Type of document:
Best practice

IETF RFC 3066, "Tags for the Identification of Languages," describes language tags for use in cases where it is desired to indicate the language used in an information object, how to register values for use in language tags, and a construct for matching such language tags. It is a best practices document for using the tags specified in ISO 639.

This document has been replaced by RFC 4646 and RFC 4647.

Workflow stage:
1.3, 1.8, 1.10
Business value:
Applicable to a broad range of applications requiring language identification, particularly computer systems: terminology, lexicography, information management, documentation archival and retrieval, information services, information technology, search engines, and multilinguistic cultural and economic exchange.
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