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
Nine-pin bowling the United States, as well as regionally popular "small-ball" bowling sports of various types, do not have many facilities in existence for the nine-pin game in the 21st century. On the other hand, a modified version is played in the US state of Texas. This game is played by rolling a ball down an alley towards nine pins. Unlike the ten-pin ball — and like the ones used for the eastern North American "small-ball" bowling sports of five pin bowling, candlepin and duckpin — the ninepin ball mostly has no holes for the fingers, though there exist special balls with