Bowling ball Bowling ball A bowling ball is a piece of sporting equipment used to hit bowling pins in the sport of bowling. Balls used in ten-pin bowling are typically hard spheres with three holes drilled in them, one each for the ring and middle fingers, and one for the thumb. Regulating bodies such as the USBC maintain requirements for the properties of bowling balls, including size, hardness, and number of holes, as well as maintaining a list of bowling balls approved for competitive play. Other bowling balls, such as those used in five-pin bowling, candlepin bowling, and duckpin bowling are smaller,
Ten-pin bowling have a decimal component (numbers to the right of the decimal point) discard all numbers to the right of the decimal point, leaving only a whole number, as rounding any decimal number equal or higher than 0.500, "up" to the next highest whole number when calculating averages is prohibited by USBC rules on scoring in tenpins. As of the 2014–15 season, approximately 1.57 million people compete in bowling leagues in the United States. At its peak in 1980, over eight million men and women competed in leagues throughout the United States. In ten-pin bowling there are two major world organizations