World Chess Federation. It is called FIDE because of its French acronym Federation Internationale des Echecs. FIDE was founded in Paris, France on July 24, 1924. Its motto is Gens una sumus, which is "We are all one family".
FIDE is recognized as the supreme international body, responsible for the game of chess. It unites 185 (number is changeable) National Chess Federations around the world. The organization has its own flag and anthem, the official ones.
All national federations conduct chess tournaments in their countries under the auspices of FIDE and then send the tournament results. FIDE calculates, and at the beginning of each month publish the ratings of all chess players on the FIDE website.