ICAO : ICAO is the International Civil aviation Organisation. It works on a sustainable development of civil aviation for safe and secure international air transport through the cooperation of its member states. Its headquarters is located in Montreal, Canada. There are 193 ICAO member states at present. ICAO is a standards organization. ICAO has standardized some functions of the airline industry like Aeronautical Message Handling System. It has also defined International Standard Atmosphere. ICAO has its own airport and airline code system.

IATA : IATA is the International air transport association. It is a trade association of the airline companies of the world which sets up technical standards, and also helps to formulate industry policy. Its headquarter is located in Montreal, Canada. IATA gives international airlines a mechanism to fix prices. IATA has its focus area on safety and has its IATA Operational Safety Audit. It also helps the airline by simplifying the airline businesses. IATA has its own airline and airport code system.