• ISO 3166-1 alpha-2, a two-letter system, used in many applications, most prominently for country code top-level domains (ccTLDs), with some exceptions.
• ISO 3166-1 alpha-3, a three-letter system, which allows a better visual association between country name and code element than the alpha-2 code.
• ISO 3166-1 numeric, a three-digit numerical system, with the advantage of script (writing system) independence, and hence useful for people or systems which uses a non-Latin script. This is identical to codes defined by the United Nations Statistics Division.

ISO 3166 has included alphabetical country codes since its first edition in 1974, and numeric country codes since its second edition in 1981. The country codes were first published as ISO 3166-1 in 1997 in the fifth edition of ISO 3166, when ISO 3166 were divided into three separate parts.

ISO 3166-1 is not the only standard for country codes. Many international organizations use their own country codes, where some of them closely correspond to the ISO 3166-1 codes. For examples, see country codes.

Criteria for inclusion

• United Nations Terminology Bulletin, Country Names, or
• Country and Region Codes for Statistical Use of the UN Statistics Division.

To be listed in the bulletin Country Names, a country must either be:

• a member country of the United Nations,
• a member of one of its specialized agencies, or
• a party to the Statute of the International Court of Justice.

The list of names in the code of the UN Statistics Division is based on the bulletin Country Names and other UN sources.

Once a country name or territory name appears in either of these two sources, it will be added to ISO 3166-1 by default.

Information included

1. COUNTRY NAME English (or French) short name
2. English (or French) short name lower case
3. English (or French) full name
4. Alpha-2 code
5. Alpha-3 code
6. Numeric code
7. Remarks
8. Independent (# denotes the country is independent)
9. Additional information (official language alpha-2 codes)
10. Additional information (official language alpha-3 codes)
11. Additional information (local name)

Officially assigned code elements

Reserved and user-assigned code elements

Reserved code elements are codes which, while not ISO 3166-1 codes, are in use for some applications in conjunction with the ISO 3166 codes. They are reserved to add flexibility to the coding system. Usually, obsolete codes may be kept as reserved, while some overseas territories, international organizations, and special nationality status have reserved codes of their own. See the corresponding sections in ISO 3166-1 alpha-2 and ISO 3166-1 alpha-3 for their respective reserved codes (ISO 3166-1 numeric does not have reserved codes).

User-assigned code elements are codes at the disposal of users who need to add further names of countries, territories or other geographical entities to their in-house application of ISO 3166-1, and the ISO 3166/MA will never use them in the updating process of the standard. See the corresponding sections in ISO 3166-1 alpha-2, ISO 3166-1 alpha-3 and ISO 3166-1 numeric for their respective user-assigned codes.

Changes

Changes to ISO 3166-1 are announced in newsletters by ISO 3166/MA. 12 newsletters were released between the first and second editions of ISO 3166-1 (published in 1997 and 2006 respectively):

1. Newsletter V-1 – Published 1998-02-05: Change of official name (Samoa).
2. Newsletter V-2 – Published 1999-10-01: Inclusion of new country name and code elements (Palestinian Territory, Occupied).
3. Newsletter V-3 – Published 2002-02-01: Change of alpha-3 Code Element (Romania).
4. Newsletter V-4 – Published 2002-05-20: Name changes (Afghanistan, Azerbaijan, Bahrain, Bosnia and Herzegovina, Fiji, Hong Kong, Kazakhstan, Kiribati, Macao, Niue, Somalia, and Venezuela).
5. Newsletter V-5 – Published 2002-05-20: Change of names and alphabetical code elements of East Timor.
6. Newsletter V-6 – Published 2002-11-15: Change of names of East Timor (to Timor-Leste).
7. Newsletter V-7 – Published 2002-11-15: Change of official name of Comoros.
8. Newsletter V-8 – Published 2003-07-23: Deletion of "Yugoslavia"; inclusion of "Serbia and Montenegro" with new alphabetical code elements.
9. Newsletter V-9 – Published 2004-02-13: Inclusion of an entry for Åland Islands.
10. Newsletter V-10 – Published 2004-04-26: Name changes (Afghanistan and Åland Islands).
11. Newsletter V-11 – Published 2006-03-29: Inclusion of an entry for Jersey, Guernsey and Isle of Man. Change of remark for the United Kingdom.
12. Newsletter V-12 – Published 2006-09-26: Inclusion of the new entries for "Serbia" and "Montenegro" (replacing Serbia and Montenegro).

The second edition of ISO 3166-1 comprised a consolidation of all changes from the first edition as published in the newsletters from V-1 to V-12. Two newsletters have been released since the second edition of ISO 3166-1 was published:

1. Newsletter VI-1 – Published 2007-09-21: Assignment of code elements for Saint Barthélemy and Saint Martin and update of France and other French Territories (French Polynesia, French Southern Territories, Guadeloupe, and Réunion).
2. Newsletter VI-2 – Published 2008-04-08: Name changes for Moldova, Montenegro and other minor corrections (Madagascar, Palestinian Territory, Occupied, and Saint Barthélemy).

References