A pitch, in baseball, is when a pitcher throws the baseball to the batter. This is a pitcher's main job. The pitcher tries to get the player who is at-bat out. If a pitcher throws three strikes, the batter strikes out (unless the third strike is a foul tip). A strike is when a pitch is in the zone from the batter's knees to the belt and the width of home plate (the strike zone), and if the batter does not swing. A strike is also called if a batter swings at any pitch and misses, or if a batter hits a ball into foul territory (this is called a foul tip). If a pitcher throws a ball outside of the strike zone and the batter does not swing, this is called a ball. If four of these are thrown, the batter gets to go to first base for free. This is called a walk.
Pitchers use different pitches to try to get the batter out. The most common is a fastball. A fastball is when the pitcher throws the ball as hard as he or she can. The pitcher is trying to get the ball past the batter before the batter can hit it. Another type of pitch is a changeup. A pitcher throws a changeup when he or she wants the batter to swing before the ball gets to home plate. The batter might do this because he or she thinks the pitch is a fastball and the baseball will get to the plate faster. In addition to these two types of pitches, there are also many others.