March Madness in basketball is a term used to describe the National Collegiate Athletic Association (NCAA) Division I Basketball Tournament, which is held every year throughout mid-March and early April. It is the playoffs for men's college basketball at the division 1 level and is one of the most highly watched sporting events in the world. It features 68 teams from across the country competing to win the national championship and be crowned the best team in college basketball for that season.
As previously mentioned, March Madness has 68 teams that are involved. 32 teams in the field are automatically invited based on their postseason success in their respective conferences. So, the 32 conference winners are included as well as 36 teams chosen "at-large" or by the selection committee that meets the Sunday before the tournament begins. A few factors go into the selection of these teams including strength of schedule, conference success, and non-conference opponents. Once the field is set, a single elimination tournament begins with a round including 8 teams to start playing for 4 spots. Once these "final four" teams to be included into the field are settled into two spots the main tournament begins with 64 teams. The rounds decrease the amount of teams from 64 to 32 to the sweet 16 to the elite 8 to the final 4 to the championship 2 to the champion.
The first March Madness tournament was held in 1939 and had 8 teams invited. The field expanded to 16 in 1951, and reached its 64-team format by 1985. In 2001, the field was bumped to 65 with one play-in game because of the addition of the Mountain West Conference. 3 more teams were added to make 68 in 2011 and this makes four play-in or "first four" games. 36 different schools have won a March Madness tournament or the national championship. UCLA owns the most championships with 11 while other notable schools are Duke University with 5, North Carolina with 6, Kentucky with 8, and Villanova with 3 and 2 of the last 4.