The International Air Transport Association (IATA pronounced [aɪˈɑːtə], English for International Air Transport Association) was founded as the umbrella organization for airlines in Havana, Cuba, in April 1945. IATA seeks to simplify processes in the aviation business.
The International Civil Aviation Organization (ICAO) is a specialized agency of the United Nations (UN) with headquarters in Montreal, Canada. The organization’s goal is to promote sustainable growth of the global civil aviation system.
The IATA airport code (or sometimes IATA (Airport) Three Letter Code, (AP)3LC) is a code developed by the International Air Transport Association (IATA) to uniquely identify airports. It consists of a combination of three alphabetical characters. For example, MUC stands for Munich Airport, AGB for Augsburg Airport or BER for Berlin Brandenburg “Willy Brandt” Airport.
ICAO codes are used to uniquely identify airports, heliports, airlines and aircraft types. They are assigned by the International Civil Aviation Organization (ICAO). ICAO codes are used by air traffic control, in flight planning as well as in flight operations.
The first letter indicates the region/continent, or in some cases the country, in which the airfield is located.
The second letter usually indicates the country (e.g. ED=Germany, LO=Austria, LS=Switzerland, EG=United Kingdom). Germany is one of a few countries to have two first combinations, where ED stands for civil airfields and ET for military airfields. This is based on the fact that ET used to stand for the German Democratic Republic.
The last two characters (for countries represented by only one letter, the last three) are used to assign airports within the respective countries. Their meanings are regulated differently depending on the country.