Teams can change pitchers during a game. Teams change their pitchers often because it is hard for a pitcher to throw a full game of nine innings. A pitcher can sometimes throw a no-hitter where no one on the opposite team gets an earned hit. A team can use as many pitchers as it wants to, but it is rare to use more than eight in a game. The ways that a pitcher throws the ball are called "pitches". Many professional pitchers use two or more different pitches. Pitchers change which pitch they throw so that the batter will be tricked and not know what pitch to expect. This makes it more difficult for the batter to hit the ball. Pitchers can make the ball move differently: faster or slower, closer or farther from the batter, higher or lower. There are also many types of pitches, such as the slurve, curve, slider, splitter, sinker, screw, 2-seam cut, 2-seam screw, knuckle, knuckle curve, change-up, circle change-up, palm ball, and others.