Cite this BCP: TXT

BCP 47 contains the following RFCs:
NumberFilesTitleAuthorsDateMore InfoStatus
RFC 4647, BCP 47    Matching of Language TagsA. Phillips, Ed., M. Davis, Ed.September 2006Obsoletes RFC 3066Best Current Practice
RFC 5646, BCP 47    Tags for Identifying LanguagesA. Phillips, Ed., M. Davis, Ed.September 2009Obsoletes RFC 4646, ErrataBest Current Practice

Abstract of RFC 4647

This document describes a syntax, called a "language-range", for specifying items in a user's list of language preferences. It also describes different mechanisms for comparing and matching these to language tags. Two kinds of matching mechanisms, filtering and lookup, are defined. Filtering produces a (potentially empty) set of language tags, whereas lookup produces a single language tag. Possible applications include language negotiation or content selection. This document, in combination with RFC 4646, replaces RFC 3066, which replaced RFC 1766. This document specifies an Internet Best Current Practices for the Internet Community, and requests discussion and suggestions for improvements.

Abstract of RFC 5646

This document describes the structure, content, construction, and semantics of language tags for use in cases where it is desirable to indicate the language used in an information object. It also describes how to register values for use in language tags and the creation of user-defined extensions for private interchange. This document specifies an Internet Best Current Practices for the Internet Community, and requests discussion and suggestions for improvements.


For the definition of Status, see RFC 2026.

For the definition of Stream, see RFC 8729.




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