International Air Transport Association airport code

IATA airport codes are internationally recognized three-letter sequences used to indicate an airport. While some codes follow a pattern of using the first three letters of the city such airport serves, (ex, ATL for Atlanta, MEX for Mexico city and so on); others follow less organized patterns. (ex, DTW for Detroit–Wayne County Metropolitan Airport, RDU for Raleigh–Durham, MSP for Minneapolis–Saint Paul) Not to be confused with International Civil Aviation Organization airport codes.