3x3 (pronounced 3 on 3), previously known as FIBA 33, is a formalized version of three-on-three basketball. It is a form of the game initially developed on inner-city asphalt outdoor courts in the United States. With over 250 million players worldwide and among the most played recreational sports in the world, 3x3 will become a key motor for the growth of basketball. This variant of the sport is currently being promoted by the sport's worldwide governing body, FIBA, which began developing it in 2007. The format was first tested at the 2007 Asian Indoor Games in Macau, introduced at international level at the 2009 Asian Youth Games in Singapore, and made its worldwide competitive debut at the 2010 Youth Olympics, also in Singapore.

FIBA released its official rules for FIBA 3x3 on June 2, 2010 as a supplement to its official basketball rules. The rules state that regular FIBA rules apply to all situations not specifically addressed in the FIBA 3x3 rules.

The departures from regular full-court basketball are as follows:

3x3 is a typeface based on a 3x3 bitmap matrix. It was created by type designer Anders de Flon, who long refused to release the typeface, due to the large type foundries' demand for only complete typefaces, which means upper and lower case characters, exclamation marks, etc.

The typeface has appeared on several record sleeves; a slightly modified version appears on the cover of LFO's Sheath, designed by The Designers Republic.

A similar typeface named 3x3 but not adhering to a 3x3 bitmap matrix was designed by Swiss graphic designer Marc Beekhuis in 2001.

Basketball is a team sport, the objective being to shoot a ball through a basket horizontally positioned to score points while following a set of rules. Usually, two teams of five players play on a marked rectangular court with a basket at each width end. Basketball is one of the world's most popular and widely viewed sports.

A regulation basketball hoop consists of a rim 18 inches in diameter and 10 feet high mounted to a backboard. A team can score a field goal by shooting the ball through the basket during regular play. A field goal scores two points for the shooting team if a player is touching or closer to the basket than the three-point line, and three points (known commonly as a 3 pointer or three) if the player is behind the three-point line. The team with the most points at the end of the game wins, but additional time (overtime) may be issued when the game ends with a draw. The ball can be advanced on the court by bouncing it while walking or running (dribbling) or throwing (passing) it to a teammate. It is a violation to move without dribbling the ball (traveling), to carry it, or to double dribble (to hold the ball with both hands then resume dribbling).