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A football is a ball used to play one of the sports known as football.
As the term football has diverged, the name of the ball itself may refer to one of two basic shapes:
Ball Used in Football/Soccer
The ball used in football (soccer) is called a football or soccer ball. Law 2 of the game specifies the ball to be an air-filled sphere with a circumference of 68–70 cm (or 27–28 inches), a weight of 410–450 g (or 14–16 ounces), inflated to a pressure of 60–110 kPa (or 8.5–15.6 psi), and covered in leather or "other suitable" material. [1]
Modern balls are stitched from 32 waterproofed panels, 12 regular pentagons and 20 regular hexagons. The first such was the Adidas Telstar ball, the official ball of the Mexico World Cup in 1970. The Telstar's design of black pentagon/white hexagon has become the archetype, still used for generic balls and symbolic representations of the game. However premium branded balls, such as the Nike Total 90 Aerow and Total 90 Aerow Hi-Vis (the official ball of the English Premiership in 2005), have other more elaborate patterns.
The 32-panel configuration is similar to the polyhedron known as the truncated icosahedron, except that it is more spherical, because the faces bulge due to the pressure of the air inside. It can be also described as a model for the buckminsterfullerene (C60) molecule. The diameter of the football and the Buckminsterfullerene molecule are 22 cm and ca. 1 nm, respectively, hence the size ratio is 200,000,000 : 1.
The standard ball is a Size 5. Smaller sizes exist; Size 3 is standard for team handball; others are used in underage games or as novelty items. Traditional, pre-1970, balls were monochrome (brown or white); they were stitched from 18 oblong non-waterproof leather panels, similar to the design of modern volleyballs and gaelic footballs, and laced to allow access to the internal air bladder. There are also indoor footballs, which are made of one or two pieces of plastic. Often these have designs printed on them to resemble a leather ball.
80% of footballs are made in Pakistan, mainly in small workshops and factories. FIFA and the major sports brands have taken public steps in response to concerns been raised about the use of child labour in the manufacture of footballs. [2]
Ball Used in Rugby and Australian Rules Football
The football used in rugby and Australian rules football is a prolate spheriod essentially elliptical in profile. Traditionally made of brown leather, modern rugby balls are manufactured in a variety of colors and patterns. A regulation rugby ball is 28–30 cm (11–11.8 inches) long and 58–62 cm (22.8–24.4 inches) in circumference at its widest point. It weighs 410–460 grams (14.5–16.2 ounces) and is inflated to 65.71–68.75 kPa (or 9.5–10 psi). [3]
Ball Used in American and Canadian Football
In North America, the term football refers to a ball which is used to play American or Canadian football. Nearly a prolate spheroid, it is slightly pointed at the ends (unlike the more elliptical rugby ball). It is about 11 inches (28 cm) long and about 22 inches (56 cm) in circumference at the center. Balls are made of four pieces of leather stitched together. A football has a rubber lining, which is inflated to an air pressure of 12.5–13.5 psi (86–93 kPa). The ball weighs 14–15 ounces (397–425 g). Leather laces along one seam provide a grip for holding and passing the ball. Footballs used in recreation may be made of rubber or plastic as well. Regardless of the material used to make it, the ball is sometimes colloquially referred to as a pigskin.
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