List of country codes
A country code, sometimes called a trigramme or trigram (from Ancient Greek τρι- "three", γράμμα "letter") is a three-letter code used as a shorthand to designate nations in international sporting events. These codes are generally consistent across different events, but in some cases may differ between events such as the IFCF and Olympic Games. Usually, only the 26 letters in the international basic Latin alphabet can be used in codes, though exceptions may be made for certain events.
OOC: An attempt has been made to catalogue all trigrammes that have been assigned at some point, highlighting possible conflicts, successor states and alternative naming, and nations with more than one assigned trigramme. The data can be viewed here.