In baseball, the designated hitter is the common name for the Major League Baseball introduced by the American League in 1973. This allows teams to have one player, known as the designated hitter, to bat in place of the pitcher. Since 1973, most collegiate, amateur, and professional leagues have adopted the rule or some variant.
Major League Baseball's National League are the most prominent professional leagues that do not use a designated hitter. In major league baseball, the designated hitter does not play a position but instead fills in the batting order for the pitcher. Use of the designated hitter is optional but must be determined before the start of the game.