This is a list of FIPS 10-4 country codes for Countries, Dependencies, Areas of Special Sovereignty, and Their Principal Administrative Divisions.
The two-letter country codes were used by the US government for geographical data processing in many publications, such as the CIA World Factbook.
3 (Nov 2003) and as DIA 65-18 (Defense Intelligence Agency, 1994, "Geopolitical Data Elements and Related Features").
The FIPS standard includes both the codes for independent countries (similar but often incompatible with the ISO 3166-1 alpha-2 standard) and the codes for top-level subdivision of the countries (similar to but usually incompatible with the ISO 3166-2 standard).
[1][2] It was replaced in the U.S. Government by the Geopolitical Entities, Names, and Codes (GENC), which is based on ISO 3166.