ISO 639 is a multi-part standard by the International Organization for Standardization (ISO) concerned with representation of names for languages and language groups.
It currently consists of five parts (1-5); a part 6 was published but withdrawn.
It was first approved in 1967 as a single-part ISO Recommendation, ISO/R 639, superseded in 2002 by part 1 of the new series, ISO 639-1