The Pan-American or Pan American Games (also known colloquially as the Pan Am Games) is a major sporting event in the Americas featuring summer sports, in which thousands of athletes participate in a variety of competitions. The competition is held among athletes from nations of the Americas, every four years in the year before the Summer Olympic Games. The only Winter Pan American Games were held in 1990. The Pan American Sports Organization (PASO) is the governing body of the Pan American Games movement, whose structure and actions are defined by the Olympic Charter.