American football American football American football, referred to as football in the United States and Canada and also known as gridiron, is a team sport played by two teams of eleven players on a rectangular field with goalposts at each end. The offense, which is the team controlling the oval-shaped football, attempts to advance down the field by running with or passing the ball, while the defense, which is the team without control of the ball, aims to stop the offense's advance and aims to take control of the ball for themselves. The offense must advance at least ten yards in four
American football field American football field American football games are played on a rectangular "Field of Play" that measures long between goal lines, and () wide. In addition, there are end zones extending another past the goal lines to the "end lines", for a total length of . When the "football field" is used as unit of measurement, it is usually understood to mean , although technically the full length of the official field, including the end zones, is . White markings on the field identify the distance from the end zone. Inbound lines, or hash marks, are short parallel lines that mark