duties and functions of IATA?

Answer 1

IATA - The International Air Transport Association (IATA) is its global trade organisation.

Over 60 years, IATA has developed the commercial standards that built a global industry. Today, IATA’s mission is to represent, lead and serve the airline industry. Its members comprise some 260 airlines - the world’s leading passenger and cargo airlines among them - representing 94 percent of international scheduled air traffic

IATA has two primary roles: a forum for airlines to discuss common concerns and to establish standards (like the three-letter airport codes). It is not a governmental organization, but it does feed input to various government agencies (and politicians) to get what it thinks might be needed. It can also bring sanctions against airlines (and airports) which fail to meet standards. It is an organization of airlines

Answer 2

http://www.iata.org/

http://en.wikipedia.org/wiki/IATA