In baseball, the batting order or batting lineup is the sequence in which the members of the offense take their turns in batting against the pitcher. The batting order is the main component of a team's offensive strategy. In Major League Baseball, the batting order is set by the manager, who before the game begins must present the home plate umpire with two copies of his team's lineup card, a card on which a team's starting batting order is recorded. The home plate umpire keeps one copy of the lineup card of each team, and gives the second copy to the opposing manager. Once the home plate umpire gives the lineup cards to the opposing managers, the batting lineup is final and a manager can make changes only under the Official Baseball Rules governing substitutions. If a team bats out of order, it is a violation of baseball's rules and subject to penalty.
Lineup card from a 2001 spring training game between the St. Louis Cardinals and Atlanta Braves
Baseball is a bat-and-ball sport played between two teams of nine players each, taking turns batting and fielding. The game occurs over the course of several plays, with each play generally beginning when a player on the fielding team, called the pitcher, throws a ball that a player on the batting team, called the batter, tries to hit with a bat. The objective of the offensive team is to hit the ball into the field of play, away from the other team's players, allowing its players to run the bases, having them advance counter-clockwise around four bases to score what are called "runs". The objective of the defensive team is to prevent batters from becoming runners, and to prevent runners' advance around the bases. A run is scored when a runner legally advances around the bases in order and touches home plate.
Los Angeles Angels center fielder Mike Trout hits a home run on a pitch from New York Mets pitcher Tommy Milone on May 21, 2017.
2013 World Baseball Classic championship match between the Dominican Republic and Puerto Rico, March 20, 2013
David Ortiz, the batter, awaiting a pitch, with the catcher and umpire
A shortstop tries to tag out a runner who is sliding head first, attempting to reach second base.