what is a cutter pitch

A cutter pitch is a type of fastball in baseball that is designed to move slightly toward the pitchers glove side as it reaches home plate. It is a pitch that breaks toward the pitchers glove-hand side, making it very hard for left-handed batters to square the ball up. The cutter is typically 2-5 mph slower than a pitchers four-seam fastball. It is usually thrown faster than a slider and somewhere between a slider and a four-seam fastball. The cutter is a contact pitch that is not intended to be a swing and miss pitch, but rather to induce weak contact. The pitch is named after its ability to "cut" through the air and move in on the hands of the batter. The cutter has been around since at least the 1950s, but it gained popularity in the 1990s when Mariano Rivera, one of the foremost practitioners of the cutter, made the pitch famous.