College football is American football played by teams of student athletes fielded by American universities, colleges, and military academies, or Canadian football played by teams of student athletes fielded by Canadian universities. It was through college football play that American football rules first gained popularity in the United States.
American football (known as football in the United States and gridiron in some other countries) is a sport played by two teams of eleven players on a rectangular field 120 yards long by 53.33 yards wide with goalposts at each end. The offense attempts to advance an oval ball (the football) down the field by running with or passing it. They must advance it at least ten yards in four downs to receive a new set of four downs and continue the drive; if not, they turn over the football to the opposing team. Points are scored by advancing the ball into the opposing team's end zone for a touchdown, kicking the ball through the opponent's goalposts for a field goal or by the defense tackling the ball carrier in the offense's end zone for a safety. The team with the most points at the end of a game wins.
American football evolved in the United States, originating from the sport of rugby football. The first game of American football was played on November 6, 1869 between two college teams, Rutgers and Princeton, under rules resembling rugby and soccer. A set of rule changes drawn up from 1880 onward by Walter Camp, the "Father of American Football", established the snap, eleven-player teams and the concept of downs, and later rule changes legalized the forward pass, created the neutral zone and specified the size and shape of the football.