H-O-R-S-E

Variations of basketball are games or activities based on, or similar in origin, to the game of basketball, in which the player utilizes common basketball skills. Some are essentially identical to basketball, with only minor rules changes, while others are more distant and arguably not simple variations but distinct games. Other variations include children's games, contests or activities intended to help the player practice or reinforce skills, which may or may not have a competitive aspect. Most of the variations are played in informal settings, without the presence of referees or other officials and sometimes without strict adherence to official game rules.

An actual competitive game of basketball can be played with as few as two people. The game may be referred to by the number of people on each team; a six-player game may be referred to as "three-on-three" or "3-v-3" ("v" stands for "versus"). Each team's roster is typically the same size, but an odd number of players may force one team to play with one less player. Sometimes the odd player will be designated as a "switch" player, so that the offensive team always has the extra player.

Roster sizes above five players per team are uncommon even in informal games, as the court generally becomes too crowded to allow movement and space to develop between players.

Six-on-six basketball was a form of basketball played in the twentieth century mainly among high school girls.

Three-on-three basketball remains competitively played by amateurs. More recently, FIBA has created a formalized version of three-on-three, originally known as FIBA 33 and now called 3x3.

"Twenty-one" is a game that can be played with two or more players. Each player has their own score, with the winner being the first to reach 21 points. No player has any teammates at any time in the game. The player with the ball may shoot at any time, and may collect his own rebound and shoot again. Whenever a basket is scored, that player receives two points and goes to the free throw line, where each made free throw tacks on another one point to their score. The player is allowed to shoot free throws until he misses, or until he has made 3 in a row, at which point the ball is put back in play, and the sequence starts again. Twenty-one is nearly always played in a half court game.

Spin-offs from basketball that are now separate sports include:

Ringball is a traditional South African sport that stems from basketball and has been played since 1907. The sport is now promoted in South Africa, Namibia, Botswana, Lesotho, India, and Mauritius to establish Ringball as an international sport.

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