The football playing field is rectangular in shape, measuring 100 yd long and 53.5 yd (48.9 m) wide. At both ends of the 100-yard dimension, white lines called goal lines mark off the entrances to the end zones. Each team defends one end zone. A team must carry, pass, or kick the ball into the 10-yd end zone on the opponents' half of the field to score. Lines parallel to the end zones cross the field at 5-yd intervals. These lines give the field a resemblance to a large gridiron. Another set of lines, known as the sidelines, runs along both sides of the field. In addition, two rows of lines, called hash marks, run parallel to the sidelines.

The hash marks are 53 ft 4 in from each sideline and 70 ft 9 in from each sideline in the National Football League (NFL). Each play must begin on or between the hash marks. Before each play, the officials place the ball either between the hash marks or on the hash mark closest to the end of the previous play. Situated in the middle of the rear line of each end zone are goalposts, consisting of a 10-ft vertical pole topped by a horizontal crossbar from which two vertical upright posts extend. In college and professional football, the posts are 18 ft 6 in  apart. The football consists of an inflated rubber bladder encased in a leather or rubber cover. The ball is an extended spheroid, having a circumference of 28.5 in around the long axis and 21.25 in around the short axis. It weighs between 14 to15 oz .         

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