A baseball bat is a smooth wooden or metal club used in the sport of baseball to hit the ball after it is thrown by the pitcher. By regulation it may be no more than in diameter at the thickest part and no more than in length. Although historically bats approaching were swung, today bats of are common, topping out at to . Terminology A baseball bat is divided into several regions. The "barrel" is the thick part of the bat, where it is meant to hit the ball. The part of the barrel best for hitting the ball, according to construction and swinging style, is often called the "sweet spot." The end of the barrel is called the "top," "end," or "cap" of the bat. Opposite the cap, the barrel narrows until it meets the "handle," which is comparatively thin, so that batters can comfortably grip the bat in their hands. Sometimes, especially on metal bats, the handle is wrapped with a rubber or tape "grip". Finally, below the handle is the "knob" of the bat, a wider piece that keeps the bat from slipping from a batter's hands. "Lumber" is an often-used slang term for a bat, especially when wielded by a particularly able batter. The "bat drop" of a bat is its weight, in ounces, minus its length, in inches. For example, a 30-ounce, 33-inch-long bat has a bat drop of minus 3 (30 − 33 = −3). Larger bat drops help to increase swing speed; smaller drops create more power. History The bat's form has become more refined over time. In the mid-19th century, baseball batters were known to shape or whittle their own bats by hand, which resulted in a wide range of shapes, sizes, and weights. For example, there were flat bats, round bats, short bats, and fat bats. Earlier bats were known to be much heavier and larger than today's regulated ones. During the 19th century, many shapes were experimented with, as well as handle designs. Today, bats are much more uniform in design. Innovations On June 17, 1890, Emile Kinst patented the ball-bat, or banana bat. The bat is shaped with a curve, hence the name banana bat. The creator of the bat, Kinst wrote: "The object of my invention is to provide a ball-bat which shall produce a rotary or spinning motion of the ball in its flight to a higher