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,
Five-pin bowling bowlers use a number of terms to denote the results of a throw: All modern bowling centres use automated pin-setting machines (first used in 1957) to reset the pins after each ball is thrown. In five-pin, two types of pinsetters are used—"string" and "free fall". The "string" pinsetter is known for each pin having a string attached to the head. These pinsetters were first invented in 1963 and are characterized by a string being attached to the head of each pin. This type of pinsetter has a low operating cost, so it is the most commonly used type of pinsetter.