ISO 639-3 is in process of development as an international standard for language codes. It extends the alpha-3 code in ISO 639-2 with an aim to cover all known languages. It is, therefore, a superset of ISO 639-1 and of the individual languages in ISO 639-2. Part 2 also includes language collections, whereas Part 3 does not, so 639-3 is not a superset of 639-2.
The draft from 2005-07-30 contains 7602 entries. The inventory of languages is based on three sources: the individual languages contained in 639-2 are the basis, this was extended by modern languages from the Ethnologue 15th edition, and by historic varieties, ancient languages and artificial languages from the Linguist List.
The status of this project from January 2005 is that of Draft International Standard (DIS). The current draft is referred to as ISO/DIS 639-3.
Code space
Since the code is three letter alphabetic one upper bound for the number of languages that can be represented is 26 × 26 × 26 = 17 576. Since ISO 639-2 defines special codes (2), a reserved range (520) and B-only codes (23), 545 codes cannot be used in part 3. Therefore a lower bound is 17 576 - 545 = 17 032.
From this number the number of language collection codes in part 2 can be subtracted to get a next lower upper bound for part 2.
Macrolanguages
Some ISO 639-2/T codes that are commonly used for languages do not precisely represent this language in 639-3, because they are regarded as macrolanguages, or collections.
See also: http://www.sil.org/iso639-3/scope.asp#M , http://www.sil.org/iso639-3/macrolanguages.asp
See also
External links
The content of this page is retrieved from http://en.wikipedia.org/wiki/ISO_639-3 under GFDL
