Bowling form Bowling form In the sport of ten-pin bowling, there are many different ways in which to deliver (known as a "throw" or "roll") the bowling ball in order to advance it toward the pins in an accurate and powerful manner. Generally, there are three basic forms of 10-pin bowling. The most basic form is known as stroking, which is the most classic form. The most powerful form is known as cranking, which imparts great leverage and maximum rotation on the ball, but sacrifices accuracy. In between the two is the domain of the tweener, who has characteristics of both, but
Bowling ball diameter in the range of to . The surface of the ball is required to include markings to indicate the manufacturer's brand name, the name of the ball, the center of gravity (before drilling), the orientation of the core (the Pin), and the axes of the high and/or low radius of gyration (as applicable). Additionally, markings must include an individual serial number and the logo of the USBC. Holes are allowed to be drilled into a bowling ball for a variety of reasons, and bowlers must be able to demonstrate that such holes can be used as claimed. Up to