This part of ISO 639 provides a code consisting of language code elements comprising three-letter language identifiers for the representation of languages. The language identifiers according to this part of ISO 639 were devised for use in a wide range of applications, especially in computer systems, where there is potential need to support a large number of the languages that are known to have ever existed. Whereas ISO 639-1 and ISO 639-2 are intended to focus on the major languages of the world that are most frequently represented in the total body of the world's literature, this part of ISO 639 attempts to provide as complete an enumeration of languages a