篮球共有多少号？
1.NBA和NCAA的号码解释 NCAAMen's basketball teams are allowed to have up to 5 players with the same number.This is usually done by a freshman who wants to play as his high school team， and he will usually switch after his first year of eligibility is up. However there are no restrictions for NCAA women's basktball， so you will see pairs of twins playing in the same line up with different numbers. 大学男子篮比赛最多允许两个球员穿相同的编号。这通常是新生想穿自己高中队的球衣而申请的（美国很多学校有高中生入学的传统），一般会在他大学选秀完一年后更换；然而 NCAA女子篮球没有限制，所以你会看到双胞胎姐妹一起上场打比赛的情景。
2.国际篮联的号码解释 FIBA (International Basketball Federation) has strict rules about how many times each number can be used. There is also an upper limit on how many players from any one country may wear the same number. For example， if a player retires in country A but keeps his number， it cannot be issued again until at least two other players from that nation have retired or been released from their contract. In order to comply with these requirements， NBA teams are only given a certain number of “officially recognized” jerseys per season， which they must then assign to players as they become available. 国际篮联对每个号码的使用次数有严格的规定。对同一个国家的球员使用同一号码也有上限。比如一个球员在A国退役但保留了自己的号码，那么至少有两个其他国家球员退役或离开该队后该号码才能重新使用。因为要遵守这些规定，NBA球队每赛季只能获得一定数量的“正规”球衣，必须根据球员的出场顺序来分配。
3.其他组织的号码解释 Other organizations， such as college conferences， high schools， middle schools， and youth leagues， vary in what they allow. Numbers are often assigned by the organization’s rules， rather than being chosen by the players themselves. 其他组织（大学联盟、高中、初中、少儿联赛等）的规则各不一样，号码的分配往往按组织规定的程序进行，未必是球员们选择的结果。