IETF language tag

File Format
Name	IETF language tag
Ontology	Electronic File Formats Elements of File Formats IETF language tag ; ; ;

An IETF language tag is a standard identifier for a human language or dialect. It is a short string of text; an example is "en-US".

A language tag consists of a sequence of hyphen-separated subtags, which define and refine the language.

Registration of subtags is handled by IANA. Language tags are no longer registered directly.

[TODO: What exactly is the relationship between this and ISO 639?]

Specifications