A baseball bat is a smooth wooden or metal club used in the game of baseball to hit the ball after the ball is thrown by the pitcher. It is no more than 2.75 inches in diameter at the thickest part and no more than 42 inches (1067 mm) in length. It typically weighs no more than 33 ounces (1 kg). The batter uses the bat two-handed to try to hit a pitched ball fair so that he may become a runner, advance bases, and ultimately score a run or help preceding runners to score.

Terminology

Although using a stick to hit a ball is a somewhat simple concept, the bat is a complex object. It is carved or constructed very carefully to allow for a quick balanced swing, while providing power. The bat is divided into several regions. The barrel is the thick part of the bat, where the bat is meant to hit the ball. The part of the barrel best for hitting the ball with, according to construction and swinging style, is often called the sweet spot. The end of the barrel is not part of the sweet spot, and is simply called the tip or end of the bat. The barrel narrows, and becomes the handle. The handle is very thin, so that batters can comfortably set the bat in their fingers. Sometimes, especially on metal bats, the handle is wrapped with a rubber or cloth grip. Finally, next to the handle is the knob of the bat, a wider piece that keeps the bat from sliding out of a batter's hands. Over the centuries, the baseball bat's form has become more refined. During the 19th century, many shapes were experimented with, as well as handle designs. Today, the baseball bat is much more uniform in design.

"Lumber" is a sometimes-used slang term for a bat, especially when wielded by a particularly good batter.

The bat drop of a baseball 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. Bats with smaller drops create more power.

Baseball bat regulations

In professional baseball, only wooden bats are permitted, and they are not allowed to be hollowed or corked—that is, filled with an alien substance such as cork which reduces the weight, and is thought to thus increase bat speed without greatly reducing hitting power. In amateur baseball, both wooden and metal alloy bats are generally permitted. Recently there have been increasing numbers of "wooden bat leagues" and the trend back to wood seems to be accelerating due to safety concerns regarding the speed of a batted ball hit directly toward the pitcher's head. Metal (generally aluminum) alloy bats are generally regarded as being capable of hitting a ball faster and farther than wooden bats swung with the same power. Some amateur baseball organizations enforce bat manufacturing and testing standards which attempt to limit maximum ball speed for wood and non-wood bats. Aesthetically, wooden bats are generally agreed to be superior to metal bats, both because of their more traditional appearance and because a ball hit with a wooden bat makes a loud "crack" sound, while metal alloy bats have a "ping" sound.