Airport abbreviations, known as IATA (International Air Transport Association) codes, are three-letter identifiers used to distinguish airports globally and prevent confusion in ticketing and luggage handling. Many are intuitive, such as ATL for Atlanta or MEX for Mexico City. Others follow historical or geographic logic: ORD (Chicago O'Hare) stands for its former name "Orchard Field," while Canadian codes like YYZ (Toronto) use the "Y" prefix originally designated for airports with a weather reporting station. There are also ICAO (International Civil Aviation Organization) codes, which are four letters and used primarily by pilots and air traffic controllers for technical flight planning (e.g., KJFK for New York's JFK). In 2026, these codes remain the "universal language" of aviation, ensuring that when you check your bag to "SYD," it lands in Sydney, Australia, and not Sydney, Nova Scotia (YQY). Understanding these codes is the first step in "pro-traveler" navigation, helping you quickly identify your destination on boarding passes and terminal monitors.