Airport designators are abbreviated codes which are internationally recognized and used to identify airports, promote conformity, and facilitate business-to-business interaction. Airport designators are sometimes called airport codes, designator codes, or simply designators.
Most commonly, airport designators refer to those assigned by the International Air Transport Association (IATA). On airline tickets, the city pair will often be written, such as LHR › MXP, for a flight going from London’s Heathrow Airport (LHR) to Malpensa Airport in Milan (MXP). Another popular database of airport designator codes are compiled by the International Civil Aviation Organization (ICAO).
The IATA standard uses 3-digit abbreviations, such as JFK for John F. Kennedy International Airport in New York City. The ICAO standard uses 4-digit abbreviations, such as KJFK for JFK International Airport. These two organizations also offer their standardized airline designators.