Uniform number (basketball)

In team sports, the number, often referred to as the uniform number, squad number, jersey number, shirt number, sweater number, or similar (with such naming differences varying by sport and region) is the number worn on a player's uniform, to identify and distinguish each player (and sometimes others, such as coaches and officials) from others wearing the same or similar uniforms. The number is typically displayed on the rear of the jersey, often accompanied by the surname. Sometimes it is also displayed on the front and/or sleeves, or on the player's shorts or headgear. It is used to identify the player to officials, other players, official scorers, and spectators; in some sports, it is also indicative of the player's position.

The International Federation of Football History and Statistics, an organization of association football historians, traces the origin of numbers to a 1911 Australian rules football match in Sydney, although photographic evidence exists of numbers being used in Australia as early as May 1903. Player numbers were used in a Queensland vs. New Zealand rugby match played on 17 July 1897, in Brisbane, Australia, as reported in the Brisbane Courier.

In association football, numbers were traditionally assigned based on a player's position or reputation on the field, with the starting 11 players wearing 1–11, and the substitutes wearing higher numbers. The goalkeeper would generally wear number 1, then defenders, midfield players and forwards in ascending order.

Numbers being assigned to each player in a squad was initiated for the 1954 World Cup, where each man in a country's 22-man squad wore a specific number for the duration of the tournament. In 1993, England's Football Association switched to persistent squad numbers, abandoning the mandatory use of 1–11 for the starting line-up. It became standard in the FA Premier League in the 1993–94 season, with names printed above the numbers. Most European top leagues adopted the system over the next five years.

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