In baseball, a pitch is the act of throwing a baseball toward home plate to start a play. The term comes from the Knickerbocker Rules. Originally, the ball had to be literally "pitched" underhand, as with pitching horseshoes. Overhand throwing was not allowed in baseball until 1884.
Pitchers throw a variety of pitches, each of which has a slightly different velocity, trajectory, movement, and/or arm angle. These variations are introduced to confuse the batter in various ways, and ultimately aid the defensive team in getting the batter or baserunners out.
To obtain variety, and therefore enhance defensive baseball strategy, the pitcher manipulates the grip on the ball at the point of release. Variations in the grip cause the seams to "catch" the air differently, therefore changing the trajectory of the ball, making it harder for the batter to hit.
- Main article: Fastball
The fastball is the most common pitch in baseball, and most pitchers have some form of a fastball in their arsenal. It is basically a pitch thrown very fast, some with movement, some without. The cut fastball, split-finger fastball and forkball are variations on the fastball with extra movement, which are sometimes called sinking-fastballs because of the trajectories. The most common fastball type pitches are:
- Main article: Breaking ball
Well-thrown breaking balls have movement—sideways or downward usually. The goal is usually to make the ball difficult to hit well or confusing to batters. Most breaking balls are considered off-speed pitches. The most common breaking pitches are:
- Main article: Changeup
The changeup is the staple off-speed pitch, usually thrown to look like a fastball but arriving much slower to the plate. It is meant to confuse the batter's timing. The most common changeups are:
Other pitches which are or have been used in baseball are: