The NCAA Division I Men’s Basketball Tournament, also known and branded as NCAA March Madness, is a single-elimination tournament played each spring in the USA, currently comprising 64 college basketball teams in the Division I level of the National Collegiate Athletic Association (NCAA), to ascertain the national championship. The tournament was the idea of Ohio State coach Harold Olsen, and was created in 1939 from the National Association of Basketball Coaches.  Played mostly during March, it has turned into one of the most well-known sporting events in the USA. [citation ]
The championship teams comprise champions from 32 Division I conferences (that receive automatic bids), and 36 teams which are awarded at-large berths. These”at-large” teams have been chosen by an NCAA selection committee, then declared in a nationally televised event on the Sunday preceding the”First Four” play-in games, currently held in Dayton, Ohio, and dubbed Choice Sunday. The 68 teams are broken up into four regions and organized into a single-elimination”bracket”, which pre-determines, when a team wins a game, which team it will face next. Each group is”seeded”, or rated, within its area from 1 to 16. The tournament happens in impartial sites across the United States, during the course of three weekends. Teams, seeded by position, proceed through a single-game removal bracket starting with a”first four” consisting of 8 low-seeded teams playing 4 matches for a position in the first round the Tuesday and Wednesday prior to the first round starts, a primary round consisting of 64 teams playing in 32 games within the span of a week, the”Sweet Sixteen” and”Elite Eight” rounds the next weekend and week, respectively– and — to the last weekend of the tournament — the”Final Four” round. The Final Four is generally played during the weekend of April. These four teams, one from each region (East, South, Midwest, and West), compete in a preselected location for the national championship.
The championship has been televised since 1969.  Currently, the matches are broadcast by CBS, TBS, TNT, and truTV under the trade-name NCAA March Madness. Since 2011, all games are available for viewing nationwide and internationally. As television coverage has grown, so also has the popularity of the tournament. At present, millions of Americans fill out a bracket, trying to correctly predict the outcome of 63 games of the championship (not including the First Four matches ).
Together with 11 titles, UCLA gets the listing for the many NCAA Men’s Division I Basketball Championships; John Wooden coached UCLA to 10 of its 11 titles. The University of Kentucky (UK) is next, with eight national titles. The University of North Carolina is third and Duke University and Indiana University are tied for fourth with five national titles. The University of Connecticut is sixth with four national titles. The University of Kansas (KU) & Villanova are tied for 7th with three national titles. Since 1985, when the tournament expanded to 64 teams, Duke has won five championships; North Carolina and UConn have won four; Kentucky & Villanova have three; Kansas & Florida have two; and Arizona, Arkansas, Indiana, Maryland, Michigan, Michigan State, Louisville[a], Syracuse, UCLA, UNLV, and Virginia have one.