Football (ball)

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A football is a ball used to play one of the various sports known as football. In the past, crude balls made of materials such as inflated pig bladders were used. Modern balls are designed by teams of engineers to exacting specifications. Various leagues and games use different balls, though they all have one of the following basic shapes:

The precise shape and construction of footballs is typically specified as part of the rules and regulations.

Contents

American and Canadian football

In North America, the term football refers to a ball used to play American football or Canadian football (both of which developed from Rugby football). It is also referred to as a "pigskin", because of their early use of pig's bladder to cover the ball (see Medieval football).

Nearly a prolate spheroid, the ball is slightly pointed at the ends, unlike the more elliptical rugby ball. The purpose of this design is to make the ball the most efficient shape to facilitate the forward pass. The Canadian football is slightly less prolate than the American ball and has a closer resemblance to a rugby ball.

The ball is about 11 inches (28 centimetres) long and about 22 in (56 cm) in circumference at the center. American and Canadian footballs have different size standards, but those standards do overlap, making it possible for one ball to be used in either sport. The exterior of the ball is made of leather, which is required in professional and collegiate football. Footballs used in recreation, and in organized youth football, may be made of rubber or plastic materials (the high school football rulebooks still allow the inexpensive all-rubber footballs, though they are less common than leather).

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