A hit
The batter puts the ball in fair territory and reaches base without an error or a fielder’s choice. A single, double, triple, and home run all count as hits.
Guides
Rules of Baseball
The playing rules below are the definitions on the MLB.com glossary. A full game, a shortened game, and extra innings are on the innings page.
A run
A player is awarded a run when he crosses the plate. The glossary says it does not matter how he reached base. An error, a fielder’s choice, or a pinch-runner who scores still counts.
Getting on
A walk
Four pitches out of the strike zone, none of them swung at, and the batter is awarded first base. An intentional walk still counts as a walk.
Hit by a pitch
If a pitch hits the batter and he did not swing, he is awarded first base. It is not a hit. A pitch the umpire rules a strike, or a swing, cancels it. The batter has to try to avoid the pitch.
A home run
A fair ball the batter scores on, without being put out and without an error. Over the fence in fair territory, he is awarded all four bases, and runners who were on base score too.
Getting out
A strikeout
Three swinging or called strikes. A foul ball counts as a strike, but it cannot be the third strike. A foul tip the catcher holds is a third strike. If the catcher does not hold the third strike, the batter may run when first base is open, or when there are two outs.
A force
A runner who can no longer legally stay on his base has to advance. The defense can retire him by tagging the next base before he arrives. If a trailing runner is forced out first, the remaining runners have to be tagged.
An infield fly
A fair fly, not a line drive or a bunt, that an infielder can catch with ordinary effort, with runners on first and second or the bases loaded, and fewer than two outs. The batter is out even if the ball is not caught. Runners advance at their own risk.
The strike zone
The zone is the area over home plate from the midpoint between the batter’s shoulders and the top of the uniform pants, when he is in his stance, down to a point just below the kneecap. Part of the ball has to cross part of the plate in that area. The glossary says this version of the zone dates to 1996.
The pitch timer
The glossary’s 2023 rule note says the pitcher has 15 seconds with the bases empty. With runners on, the timer started at 20 seconds and was cut to 18 seconds in 2024. The pitcher has to start his motion before the timer expires, or it is a ball. A batter who is not set and alert by the eight-second mark is charged with a strike. With runners on, a pitcher is limited to two disengagements in a plate appearance.
The designated hitter
A club may use another player to bat in place of the pitcher. The pitcher stays one of the nine defensive players, and the designated hitter does not play defense. The hitter is named before the game. If that player later plays defense, or the pitcher leaves the mound for another position, the club cannot use a designated hitter for the rest of the game.
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