An IATA airport code, also known an IATA location identifier, IATA station code or simply a location identifier, 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, and it is administered by IATA headquarters in Montreal. The codes are published biannually in the IATA Airline Coding Directory. IATA also provides codes for railway stations and for airport handling entities. A list of airports sorted by IATA code is available. A list of railway stations codeshared in agreements between airlines and rail lines such as Amtrak, SNCF French Rail, and Deutsche Bahn is available. There is also a separate List of Amtrak station codes, three-character codes used by Amtrak for its railway stations in the United States and Canada.