country code

Country codes are short alphabetic or numeric geographical codes (geocodes) developed to represent countries and dependent areas, for use in data processing and communications. Several different systems have been developed to do this. The most famous of these is ISO 3166-1. The term country code frequently refers to international dialing codes, the E.164 country calling codes.
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1. In international direct telephone dialing, a code that consists of 1-, 2-, or 3-digit numbers in which the first digit designates the region and succeeding digits, if any, designate the country. 2. In international record carrier transmissions, a code consisting of 2- or 3-letter abbreviations of the country names, or 2- or 3-digit numbers that represent the country names, that follow the geographical place names.

<networking, standard> Originally, a two-letter abbreviation for a particular country, generally used as a top-level domain.
Originally, as the name implies, country codes were meant just for countries; but over time, country codes were allocated for many areas (mostly islands) that aren't countries -- such as Antarctica (aq), Christmas Island (cx) and Saint Pierre et Miquelon (pm).
Country codes are based on ISO 3166 and are used as the top level domain for Internet hostnames in most countries but hardly ever in the USA (code "us").
Latest list.
(2003-05-02)