An IATA airport code, also known an IATA location identifier, IATA station code or simply a location identifier[1], is a three-letter code designating many airports around the world, defined by the International Air Transport Association (IATA). The characters prominently displayed on baggage tags attached at airport check-in desks are an example of a way these codes are used.
The assignment of these codes is governed by IATA Resolution 763[2], and it is administered by IATA headquarters in Montreal. The codes are published biannually in the IATA Airline Coding Directory[3]. The codes are unique at any given point in time, although defunct codes may be re-used after a suitable period of time has elapsed. Many countries, such as Canada, no longer use IATA codes in their official aeronautical publications.