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 136 two-letter codes registered. The registered codes cover the world's major languages.
These codes are a useful international, and formal, shorthand for indicating languages. For example:
- English is represented by en
- French is represented by fr
- German is represented by de (from the endonym Deutsch)
- Japanese is represented by ja (even though its endonym is Nihongo)
- Portuguese is represented by pt
- Spanish is represented by es (from the endonym español)