Ten-pin bowling regulations, identification letters and numbers, and general wear from normal use. For much of the history of bowling, bowling balls were made using a three-piece construction method. Starting in the mid-1990s, however, most manufacturers switched to a two-piece method. In response to these innovative ball designs, the American Bowling Congress placed further restrictions on the technical characteristics of the ball such as the radius of gyration and hooking potential. A game of bowling consists of ten frames. In each frame, the bowler will have two chances to knock down as many pins as possible with their bowling ball. In games
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.