The NCAA Men's Division I Basketball Championship is a single elimination tournament held each spring featuring 65 college basketball teams in the United States. This tournament, organized by the National Collegiate Athletic Association (NCAA), was first developed by the National Association of Basketball Coaches in 1939 and was the brainchild of Kansas coach Phog Allen. The NCAA would take over the tournament the following season. Colloquially known as March Madness (as the tournament takes place mainly during the month of March) or the Big Dance (as opposed to the now smaller and less prestigious NIT), the tournament takes place over three weeks at sites across the United States, and the national semifinals (the Final Four) have become one of the nation's most prominent sporting events.