ISO 639-1

From MattWiki

ISO 639-1:2002, Codes for the representation of names of languages — Part 1: Alpha-2 code, is the first part of the ISO 639 series of international standards for language codes. Part 1 covers the registration of two-letter codes. There are 184 two-letter codes registered as of October 2015. The registered codes cover the world's major languages.