A football is a ball used to play one of the various sports known as football. BALL ( Biochemical Algorithms Library) is a C++ library containing common algorithms used in Biochemistry and Bioinformatics. Football is the word given to a number of similar Team sports all of which involve (to varying degrees kicking a Ball with the foot in an attempt to score a In the distant past, crude balls such as inflated pigs' bladders were used, but now high-tech balls are designed by teams of engineers to exacting specifications. Each code of football uses a different ball, though they all belong to one of two different basic shapes:
The precise shape and construction of footballs is typically specified as part of the rules and regulations. "Globose" redirects here See also Globose nucleus. A sphere (from Greek σφαίρα - sphaira, "globe Association football, more commonly known as football or soccer, is a Team sport played between two teams of eleven players and is widely considered Gaelic football ( Irish: Peil, Peil Ghaelach, or Caid) commonly referred to as " football " is a form of Football A prolate spheroid is a Spheroid in which the polar Diameter is longer than the Equatorial diameter Rugby football (usually just " rugby " may refer to a number of sports through history descended from a common form of Football developed at Rugby School Australian (rules football, or simply known as football, footy or Aussie rules, is a Team sport played between two teams of 18 players American football, known in the United States and Canada simply as football, is a competitive Team sport known for mixing strategy with In accordance with the Manual of Style (see) Canadian English is used throughout this article (see Canadian_English#Spelling)
The ball used in football is called a football. The history of association football balls is the history of the Football (ball in the game of association football. Law 2 of the game specifies that the ball is an air-filled sphere with a circumference of 68–70 cm (or 27–28 inches), a weight 410–450 g (or 14–16 ounces), inflated to a pressure of 8–12 psi, and covered in leather or "other suitable material". The Laws of the Game are the rules governing a game of Association football. "Globose" redirects here See also Globose nucleus. A sphere (from Greek σφαίρα - sphaira, "globe The circumference is the distance around a closed Curve. Circumference is a kind of Perimeter. A centimetre ( American spelling: centimeter, symbol cm) is a unit of Length in the Metric system, equal to one hundredth Inches redirects here To see the Les Savy Fav album see Inches. Mass is a fundamental concept in Physics, roughly corresponding to the Intuitive idea of how much Matter there is in an object For other uses of the words gram or gramme see Gram (disambiguation. This article is about the unit of mass For the unit of force see Pound-force. Pressure (symbol 'p' is the force per unit Area applied to an object in a direction perpendicular to the surface The pound per square inch or more accurately pound-force per square inch (symbol psi or lbf/in² or lbf/in²) is a unit of Leather is a material created through the Tanning of hides and Skins of Animals primarily Cattlehide The Tanning process  The weight specified for a ball is the dry weight, as older balls often became significantly heavier in the course of a match played in wet weather. The standard ball is a Size 5, although smaller sizes exist: Size 3 is standard for team handball and Size 4 in futsal and other small-field variants. Handball (also known as team handball, European handball, or Olympic handball) is a Team sport in which two teams of seven players each (six Futsal is an indoor version of Association football. Its name is derived from the Portuguese fut ebol de sal ão and the Spanish Other sizes are used in underage games or as novelty items.
Most modern footballs are stitched from 32 panels of waterproofed leather or plastic: 12 regular pentagons and 20 regular hexagons. The truncated icosahedron is an Archimedean solid. It comprises 12 regular pentagonal faces 20 regular hexagonal faces 60 vertices and 90 edges Leather is a material created through the Tanning of hides and Skins of Animals primarily Cattlehide The Tanning process Regular pentagons The term pentagon is commonly used to mean a regular convex pentagon, where all sides are equal and all interior angles are equal (to Regular hexagon The internal Angles of a regular hexagon (one where all sides and all angles are equal are all 120 ° and the hexagon has 720 degrees The 32-panel configuration is the spherical polyhedron corresponding to the truncated icosahedron; it is spherical because the faces bulge due to the pressure of the air inside. In Mathematics, the surface of a sphere may be divided by line segments into bounded regions to form a spherical tiling or spherical polyhedron. The truncated icosahedron is an Archimedean solid. It comprises 12 regular pentagonal faces 20 regular hexagonal faces 60 vertices and 90 edges The first 32-panel ball was marketed by Select in the 1950s in Denmark. SELECT Sport A/S is a Danish Sports equipment manufacturer It was founded in 1947 by Eigil Nielsen former goalkeeper of the Danish national football team The Kingdom of Denmark ( ˈd̥ænmɑɡ̊ (archaic ˈd̥anmɑːɡ̊ commonly known as Denmark, is a country in the Scandinavian region of northern Europe This configuration became common throughout Continental Europe in the 1960s, and was publicised worldwide by the Adidas Telstar, the official ball of the 1970 World Cup. Continental Europe, also referred to as mainland Europe or simply the Continent, is the Continent of Europe, explicitly excluding European WikipediaManual of Style (trademarks, which says "Lowercased trademarks with no internal Telstar provided by Adidas was the official match ball of 1970 FIFA World Cup and 1974 FIFA World Cup held in Mexico and West Germany The 1970 FIFA World Cup, the ninth staging of the World Cup was held in Mexico, from May 31 to June 21.
Older balls were usually 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. A volleyball is a Ball used to play Indoor volleyball, Beach volleyball, or other less common variations of the sport. This configuration is still common.
The official FIFA World Cup football for Germany 2006 matches was the 14-panel Adidas +Teamgeist. The FIFA World Cup, occasionally called the Football World Cup, but usually referred to simply as the World Cup, is an international Association football The 2006 FIFA World Cup was the 18th instance of the FIFA World Cup, the quadrennial international football world championship tournament The +Teamgeist ball was the official football for the FIFA World Cup 2006. It was made in Thailand by Adidas, who have provided the official match balls for the tournament since 1970, and is a "thermally bonded" machine-pressed ball, rather than a traditionally stitched one. The Kingdom of Thailand (ˈtaɪlænd ราชอาณาจักรไทย, râːtɕʰa-ʔaːnaːtɕɑ̀k-tʰɑj For future world cups, FIFA is hoping to alternate between Nike and Adidas for match balls.
Another ball with an innovative pattern is the 26-panel Mitre PRO 100T. Established in England in 1817 Mitre Sports International is a supplier of balls boots and accessories for football rugby netball and cricket
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 stitched leather ball.
About 80% of association footballs are made in Pakistan. Pakistan () officially the Islamic Republic of Pakistan, is a country located in South Asia, Southwest Asia, Middle East and 75% of these (60% of all world production)  are made in the city of Sialkot. Sialkot ( Urdu / Punjabi:) the capital of Sialkot District, is a city situated in the north-east of the Punjab province in In the past child labour was often used in the production of the balls. Child labor is the employment of Children at regular and sustained labour In 1996, during the European championship, activists decided to press this issue. The 1996 UEFA European Football Championship ( Euro 96) was hosted by England. This eventually led to the Atlanta Agreement, which forced ball manufacturers to make sure no child labour was involved in the fabrication of their products. The Atlanta Agreement is an agreement which was formed between the International Labour Organization, the Sialkot Chamber of Commerce and Industry and UNICEF on This also led to a centralisation of production, which on the one hand would make it easier for the Independent Monitoring Association for Child Labour (IMAC) - an organization created to watch over the Atlanta Agreement - to make sure no child labour occurred, on the other hand often forced workers to commute further to get to work. Now the production takes place primarily in small workshops and factories and is now "totally free" of child labour. 
In North America, the term football refers to a ball which is used to play American football or Canadian football (both of which developed from Rugby football). American football, known in the United States and Canada simply as football, is a competitive Team sport known for mixing strategy with In accordance with the Manual of Style (see) Canadian English is used throughout this article (see Canadian_English#Spelling) Rugby football (usually just " rugby " may refer to a number of sports through history descended from a common form of Football developed at Rugby School It is also referred to as a "pigskin", due to their early use of pig hide to cover the ball.
Nearly a prolate spheroid, the ball is slightly pointed at the ends, unlike the more elliptical rugby ball. A prolate spheroid is a Spheroid in which the polar Diameter is longer than the Equatorial diameter 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 cm) long and about 22 inches (56 cm) in circumference at the center. The exterior of the ball is made of leather, which is required in professional and collegiate football. Leather is a material created through the Tanning of hides and Skins of Animals primarily Cattlehide The Tanning process Footballs used in recreation may be made of rubber or plastic materials. Recreation or fun is the expenditure of time in a manner designed for therapeutic refreshment of one's Body or Mind. Plastic is the general common term for a wide range of synthetic or semisynthetic organic solid materials suitable for the manufacture of industrial products
Leather panels are usually tanned to a natural brown color, which is usually required in professional leagues and collegiate play. Black, when used as a general term is a color that is a Very dark Black, black, or Black, of low Luminance relative to At least one manufacturer uses leather that has been tanned to provide a "tacky" grip in dry or wet conditions. Manufacturing (from Latin manu factura, "making by hand" is the use of tools and labor to make things for use or sale Tanning is the process of converting Putrescible skin into non-putrescible Leather, usually with Tannin, an Acidic Chemical compound In general terms the Climate of a local or region is said to be arid when it is characterized by a severe lack of available Water, to the extent of hindering
The leather is usually stamped with a pebble-grain texture to help players grip the ball. Some or all of the panels may be stamped with the manufacturer's name, league or conference logos, signatures, and other markings. A brand is a collection of Images and ideas representing an economic producer more specifically it refers to the descriptive verbal attributes and concrete symbols such as a A sports league is an organization that exists to provide a regulated competition for a number of people to compete in a specific Sport. A signature (from Latin signare, " Sign " is a handwritten (and sometimes stylized depiction of someone's name nickname or even a simple
Four panels or pieces of leather or plastic are required for each football. After a series of quality control inspections for weight and blemishes, workers begin the actual manufacturing process. In Engineering and Manufacturing, quality control and quality engineering are involved in developing systems to ensure products or services In the Physical sciences weight is a Measurement of the gravitational Force acting on an object
Two of the panels are perforated along adjoining edges, so that they can be laced together. One of these lacing panels receives an additional perforation and reinforcements in its center, to hold the inflation valve. An inflatable is an object that can be inflated with a gas usually with Air, but Hydrogen, Helium and Nitrogen are also used
Each panel is attached to an interior lining. The four panels are then stitched together in an "inside-out" manner. The edges with the lacing holes, however, are not stitched together. The ball is then turned right side out by pushing the panels through the lacing hole.
A polyurethane or rubber lining called a bladder is then inserted through the lacing hole. A polyurethane, commonly abbreviated PU, is any Polymer consisting of a chain of organic units joined by urethane links
Polyvinyl chloride or leather laces are inserted through the perforations, to provide a grip for holding, hiking and passing the football.
Before play, the ball is inflated to an air pressure of 12. 5–13. 5 psi (86–93 kPa). The pound per square inch or more accurately pound-force per square inch (symbol psi or lbf/in² or lbf/in²) is a unit of The ball weighs 14–15 ounces (397–425 g). This article is about the unit of mass For the unit of force see Pound-force.
According to nfl. com: The home club shall have 36 balls for outdoor games and 24 for indoor games available for testing with a pressure gauge by the referee two hours prior to the starting time of the game to meet with League requirements. Twelve (12) new footballs, sealed in a special box and shipped by the manufacturer, will be opened in the officials’ locker room two hours prior to the starting time of the game. Elaborate wood box Tom TanakaJPG|thumb|An elaborate wooden box]] Box describes a variety of containers and receptacles These balls are to be specially marked with the letter "k" and used exclusively for the kicking game. K is the eleventh letter of the modern Latin alphabet. Its name in English is spelled kay (keɪ
The football used in Australian football is similar to a rugby ball but generally slightly smaller and more rounded. Australian (rules football, or simply known as football, footy or Aussie rules, is a Team sport played between two teams of 18 players A regulation football is 720–730 mm (28. 3–28. 7 in) in circumference, and 545–555 mm (21. 5–21. 9 in) transverse circumference, and inflated to a pressure of 62–76 kPa (9–11 psi). In the AFL, the balls are red for day matches and yellow for night matches
Different sized and weight balls are used for different age levels, and for use with other sports such as Rec Footy and Women's Australian rules football. The Australian Football League (AFL is both the professional Australian national competition in the Sport of Australian Rules Football and its highest Recreational Footy redirects here Recreational Football (also known as Rec Footy or Recreational Footy) is a non-contact version
Brands of balls used include Burley, Ross Faulkner, and the brand used in the Australian Football League, the Sherrin. Burley is a popular brand of football used in Australian rules football and made by the Burley-Sekem company The Australian Football League (AFL is both the professional Australian national competition in the Sport of Australian Rules Football and its highest Sherrin is a popular brand of football used in Australian rules football and is the official ball of the Australian Football League, designed to its official
The Australian rules ball was invented by T. W. Sherrin in 1880, after he was given a misshapen rugby ball to fix. Sherrin designed the ball with indented rather than pointy ends to give the ball a better bounce. Before this time, a round ball was used from the 1850s to 1870s and later rugby balls were used to play the game.
Gaelic football is played with a spherical leather ball, roughly 10 in (25 cm) in diameter and 27 to 29 in (69 to 74 cm) in circumference. Leather is a material created through the Tanning of hides and Skins of Animals primarily Cattlehide The Tanning process  A dry ball weighs between 370 and 425 grams (13 to 15 oz). For other uses of the words gram or gramme see Gram (disambiguation. The pattern of panels is identical to the volleyball, consisting of six groups perpendicular to each other, each group being composed of two trapezoidal panels and one rectangular panel; 18 panels in all. A volleyball is a Ball used to play Indoor volleyball, Beach volleyball, or other less common variations of the sport. A trapezoid (in North America or a trapezium (in Britain and elsewhere is a Quadrilateral (a closed plane shape with four linear sides that has at least one In Geometry, a rectangle is defined as a Quadrilateral where all four of its angles are Right angles A rectangle with vertices ABCD would be denoted as
Gaelic footballs are also the standard balls used in International rules football. International rules football (Peil na rialacha idirnáisiunta also known as inter rules in Australia and compromise rules in Ireland is a hybrid
Although Gaelic football has been played with a round ball since first organised in 1887, balls made by the Irish sports company O'Neills have been used sometime since the company was founded in 1918 and are recognised as the official ball to be played with, although it is now permitted to use the Gaelic ball manufactured by the Irish sports company Gaelic Gear. Year 1887 ( MDCCCLXXXVII) was a Common year starting on Saturday (link will display the full calendar of the Gregorian calendar (or a Common Year 1918 ( MCMXVIII) was a Common year starting on Tuesday (link will display the full calendar of the Gregorian calendar (or a Common 
Richard Lindon and William Gilbert started making balls for Rugby school out of hand stitched, four-panel, leather casings and pigs’ bladders. Richard Lindon ( 30 June, 1816 - 10 June, 1887) was instrumental in the development of the modern-day rugby football William Gilbert (1799-1877 established Gilbert (sports equipment in 1823 Rugby School, located in the town of Rugby, Warwickshire, is a Co-educational Boarding school and one of the oldest public schools The rugby ball's distinctive shape is supposedly due to the pig’s bladder though early balls were more plum shaped than oval. The balls varied in size in the beginning depending upon how large the pig’s bladder was.
Until 1870, rugby was played with a spherical ball with an inner-tube made of a pigs' bladder. In 1870 Richard Lindon introduced rubber inner-tubes and because of the pliability of rubber the shape gradually changed from a sphere to an egg. In 1892 the RFU endorsed ovalness as the compulsory shape. The Rugby Football Union (RFU is the Rugby union governing body in England The gradual flattening of the ball continued over the years. 
The introduction of synthetic footballs over the traditional leather balls, in both rugby codes, was originally governed by weather conditions. If the playing surface was heavy, the synthetic ball was used, as it didn't absorb water and become heavy. Eventually, the leather balls were phased out completely.
Rugby league is played with a prolate spheroid shaped football. History See also History of rugby league The grass roots of rugby league can be traced to early football history, through the playing of ball games Traditionally made of brown leather, modern footballs are synthetic and manufactured in a variety of colours and patterns. The football used in rugby league is known as "international size" or "size 5" and is approximately 27 cm long and 60 cm in circumference at its widest point. Smaller-sized balls are used for Mini and Mod versions of the game. A full size ball weighs between 383 and 440 grams. Rugby league footballs are slightly more pointed than rugby union footballs and larger than American footballs.
The Australian National Rugby League uses balls made by Steeden. Steeden is an Australian sports good manufacturer best known for producing Rugby league footballs Steeden is also sometimes used as a noun to describe the ball itself.
The ball used in rugby union, usually referred to as a rugby ball, is a prolate spheroid essentially elliptical in profile. In Mathematics, an ellipse (from the Greek ἔλλειψις literally absence) is a Conic section, the locus of points in a Traditionally made of brown leather, modern footballs are manufactured in a variety of colors and patterns. A regulation football 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). 
In 1980, leather-encased balls, which were prone to water-logging, were replaced with balls encased in synthetic waterproof materials.  The Gilbert Synergie was the match ball of the 2007 Rugby World Cup. The Gilbert Synergie is a Rugby union match ball produced by Gilbert. The 2007 Rugby World Cup was the sixth Rugby World Cup, a quadrennial international Rugby union world championship inaugurated in 1987.