American football
Football games last for a total of 60 minutes in professional and college play and are divided into two-halves of 30 minutes and four-quarters of 15 minutes. High school football games are 48 minutes in length with two-halves of 24 minutes and four-quarters of 12 minutes. The two-halves are separated by a halftime period, and the first and third quarters are also followed by a short break. Prior to the start of the game, the referee and team captains for each team meet at midfield for a coin toss. The visiting team is allowed to call 'heads' or 'tails'; the winner of the toss is allowed to decide between choosing whether to receive or kick off the ball or choosing which goal they want to defend, but they can also defer their choice until the second half. The losing team, unless the winning team decides to defer, is allowed to choose the option the winning team did not select, and receives the option to receive, kick, or select a goal to defend to begin the second half. Most teams choose to receive or defer, because choosing to kick the ball to start the game would allow the other team to choose which goal to defend. Teams switch goals following the first and third quarters. If a down is in progress when a quarter ends, play continues until the down is completed.
Modern history of American football
The CFP system is centered on six major bowl games played on or near New Year's Day, often called the "New Year's Six". Three pairs of games rotate annually as hosts of CFP semifinals. The champions of the so-called Power Five conferences (ACC, Big Ten, Big 12, Pac-12, SEC) all receive guaranteed berths in one of the New Year's Six games, though not necessarily in the CFP semifinals. Notre Dame, a football independent but otherwise an ACC member, has its own arrangement for access to the New Year's Six should it meet specified criteria. A selection committee similar to those used by the NCAA basketball tournaments for men and women releases a weekly ranking concurrently with the AP Poll starting with the Monday after Week 10 of the season. After the completion of the regular season, the committee selects the four teams that will compete in the CFP semifinals and the at-large entries to the New Year's Six games. One of the at-large entries is reserved for the top-ranking champion of the so-called "Group of Five" conferences (American, Conference USA, MAC, Mountain West, Sun Belt). The semifinal winners advance to the College Football Playoff National Championship game. The first season of the new system was not without controversy, however, after TCU and Baylor (each with only one loss) both failed to receive the support of the College Football Playoff selection committee.