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ISO 639

About 2 pages (654 words)

ISO 639 is the set of international standards that lists short codes for language names. ISO 639 consists of different parts, of which two parts have been approved and a third part that is in the final approval (FDIS) stage. The other parts are works in progress.

ISO 639-1: 2002 Codes for the representation of names of languages -- Part 1: Alpha-2 code List of ISO 639-1 codes
ISO 639-2: 1998 Codes for the representation of names of languages -- Part 2: Alpha-3 code List of ISO 639-2 codes
ISO 639-3: 2007 Codes for the representation of names of languages -- Part 3: Alpha-3 code for comprehensive coverage of languages List of ISO 639-3 codes
ISO/CD 639-4: 2008? Codes for the representation of names of languages -- Part 4: Implementation guidelines and general principles for language coding
ISO/DIS 639-5: 2008? Codes for the representation of names of languages -- Part 5: Alpha-3 code for language families and groups
ISO/CD 639-6: 2008? Codes for the representation of names of languages -- Part 6: Alpha-4 representation for comprehensive coverage of language variation

1 Use of ISO-639 codes
2 Alpha-2 code space
3 Alpha-3 code space
4 Alpha-4 code space
5 See also
6 External links

Use of ISO-639 codes

The language codes defined in the several sections of ISO-639 are used for bibliographic purposes and, in computing and internet environments, as a key element of locale data. The codes also find use in various applications, such as Wikipedia URLs for its different language editions.

Alpha-2 code space

"Alpha-2" codes (for codes composed of 2 letters of the basic Latin alphabet) are used in ISO 639-1. Thus, there are <math>26^2=676</math> distinct Alpha-2 codes. This is clearly insufficient to cover all languages, which led to the creation of ISO 639-2 and the use of Alpha-3 codes.

Alpha-3 code space

"Alpha-3" codes (for codes composed of 3 letters of the basic Latin alphabet) are used in ISO 639-2 and ISO 639-3 and will eventually be used in ISO 639-5. Mathematically, the upper limit for the number of languages and language collections that can be so represented is <math>26^3=17,576</math>. The common use of Alpha-3 codes by three parts of ISO 639 requires some coordination within a larger system. Part 2 defines four special codes mul, und, mis, zxx, a reserved range qaa-qtz (20 × 26 = 520 codes) and has 23 double entries (the B/T codes). This sums up to 520 + 23 + 4 = 547 codes that cannot be used in part 3 to represent languages or in part 5 to represent language families or groups. The remainder is 17,576 – 547 = 17,029. There are somewhere around six or seven thousand languages on Earth today[1][2]. So those 17,029 codes are adequate to assign a unique code to each language, although some languages may end up with arbitrary codes that sound nothing like traditional name(s) of that language.

Alpha-4 code space

"Alpha-4" codes (for codes composed of 4 letters of the basic Latin alphabet) is proposed to be used in ISO 639-6. Mathematically, the upper limit for the number of languages and dialects that can be so represented is <math>26^4=456,976</math>.