The official name of the standard is Codes for the representation of names of countries and their subdivisions – Part 2: Country subdivision code.
The purpose of ISO 3166-2 is to establish an international standard of short and unique alphanumeric codes to represent the relevant administrative divisions and dependent territories of all countries in a more convenient and less ambiguous form than their full names.
Each complete ISO 3166-2 code consists of two parts, separated by a hyphen:[1] Each complete ISO 3166-2 code can then be used to uniquely identify a country subdivision in a global context.
The codes may be alphabetic, numeric, or alphanumeric, and they may also be of constant or variable length.
Changes in ISO 3166-2 consist mostly of spelling corrections, addition and deletion of subdivisions, and modification of the administrative structure.