The World Chess Championship is played to determine the World Champion in the board game chess. Both men and women are eligible to contest this title. The official world championship is generally regarded to have begun in 1886, when the two leading players in the world played a match. From 1886 to 1946, the championship was conducted on an informal basis, with a challenger having to defeat the incumbent in a match to become the new world champion. From 1948 to 1993, the championship was administered by FIDE, the international chess organization. In 1993, the reigning champion (Garry Kasparov) broke away from FIDE, meaning there were two rival championships. This situation remained until 2006, when the title was unified at the World Chess Championship 2006. Source: World Chess Championship on Wikipedia.