ISO 3166-2:TM is the entry for Turkmenistan in ISO 3166-2, part of the ISO 3166 standard published by the International Organization for Standardization (ISO), which defines codes for the names of the principal subdivisions (e.g., provinces or states) of all countries coded in ISO 3166-1.
Currently for Turkmenistan, ISO 3166-2 codes are defined for 5 regions and 1 city. The city Ashgabat is the capital of the country and has special status equal to the regions.
Each code consists of two parts, separated by a hyphen. The first part is TM, the ISO 3166-1 alpha-2 code of Turkmenistan. The second part is a letter.
Read more about ISO 3166-2:TM: Current Codes, Changes