A Assists A player earns an assist when his thrown ball results in an out.
AB At bats The total number of plate appearances minus walks, sacrifices, hit batsmen, interference-awarded bases and obstruction-awarded bases.
AO Fly outs The total of all fly balls hit into outs against the pitcher by opposing batters, not including line drives.
AVG Average Number of hits by a player divided by the number of his official at-bats.
BB Bases on balls (walks) A batter earns first base if he takes four pitches ruled to be balls.
BK Balks An illegal motion by the pitcher, with a runner or runners on base, entitling all runners to advance one base. The intention is to catch the runners off balance.
CG Complete games Credited when the pitcher throws the entire game without any relief help.
CGL Complete game losses A pitcher is credited with a complete game loss when he is the starting pitcher for his team and is the only pitcher for his team and his team loses the game.
CS Caught stealing The number of times a baserunner was caught attempting to steal a base.
DP Double plays A defensive play in which two offensive players are put out as a result of one continuous action.
E Errors Results from a defensive player failing to field a ball that the official scorer believes the player should have caught.
ER Earned runs The total number of earned runs allowed by the pitcher. An earned run is a run for which the pitcher is held accountable, and shall be charged every time a runner reaches home base unless an error (including catcher's interference) or passed ball occurs that leads to that run.
ERA Earned run average The number of earned runs a pitcher allows, multiplied by nine and divided by the official number of innings pitched.
FLD% Fielding percentage The sum of putouts and assists divided by the sum of putouts, assists and errors.
GDP Grounded into double play The number of times a ball hit by the batter started a double play.
GF Games finished A pitcher is credited with a game finished if he is the last relief pitcher for his team in a game and was not the starting pitcher.
GO Ground outs The total of all ground balls hit into outs against the pitcher by opposing batters, not including bunts.
GO/AO Ground outs per fly out Divide the total of all ground balls hit into outs against the pitcher by opposing batters, and not including bunts, by the total of all fly balls hit into outs against the pitcher by opposing batters, and not including line drives.
GP Games played The number of games in which a player appeared.
GS Games started The number of games in which a player was in the starting lineup.
GSHR Grand slam home runs Home runs hit with runners on first base, second base and third base.
H Hits Batted balls that result in the hitter reaching base safely.
HBP Hit by pitch When a batter is awarded first base after being hit by a thrown ball by the pitcher.
HR Home runs A play in which the batter makes it safely around all bases and back to home plate without stopping.
IBB Intentional base on balls (intentional walks) When a batter is awarded first base after four balls were thrown on purpose.
INN Innings That portion of the game in which the teams alternate on offense and defense and in which there are three outs for each team. Each team's time at bat is a half-inning.
IP Innings pitched The number of innings pitched with decimals for added accuracy. A pitcher with 3.1 innings pitched had three full innings of work then retired one batter in his fourth inning of work.
IPS Innings per start The number of innings a pitcher averages each time he starts; divide total number of innings by number of starts.
IRA Inherited runs allowed Charged to a relief pitcher when he enters a game with a runner or runners on base and he allows those runners to score.
L Losses Credited to pitchers on losing teams.
LOB Left on base The number of runners on base when a team's at-bat ends.
MB9 Base runners per 9 innings The number of base runners a pitcher allows per every nine innings of work.
OBA Opponent's batting average Number of hits a pitcher allows divided by the number official at-bats he faced.
OBP On base percentage The total number of hits, walks and hit by pitches divided by the number of at-bats, walks, hit by pitches and sacrifice flies.
OFA Outfield assists Awarded to an outfielder who throws out a runner.
OPS On base percentage Plus Slugging A measure of a batter's ability to get on base and make extra-base hits; calculated by adding on-base percentage and slugging percentage; displayed with three decimal places.
P Position The place a player defends or the job he holds.
PA Plate appearances Total number of plate appearances by opposing batters against the pitcher, including all at-bats, bases on balls allowed, batters hit by pitch and sacrifice flies allowed.
PB Passed balls Given to a catcher when he fails to field a pitch resultingin a runner or runners advancing.
PK Pick-offs When a pitcher, before making a pitch, throws out a baserunner.
PO Put outs A fielder is credited with a putout if he receives the ball to put out a baserunner or a hitter.
R Runs The unit of scoring in baseball; an offensive team is credited with a run when a player crosses home plate safely.
RBI Runs batted in Awarded to a hitter when his plate appearance results in a run or runs; a hitter is not credited with an RBI if he hits into a double play or if the run is scored because of an error.
RISP Runners in scoring position Baserunners who reach second base or third base.
RW Relief wins A pitcher is credited with a relief win if he is not the starting pitcher in a game his team wins, and he is either the relief pitcher judged by the scorer to have been the most effective, or is the pitcher of record when his team assumes the lead and maintains it to the finish of the game.
RPF Relief pitcher failure When a pitcher blows a save.
SB Stolen bases The number of bases successfully stolen by a baserunner.
SF Sacrifice fly A sacrifice hit done with less than two outs, fair or foul, that allows one or more baserunners to tag up and score.
SH Sacrafice hit A ball hit that advanced the baserunner at the cost of being put out.
SHO Shutouts Credited to a pitcher when he throws a complete game without allowing a run.
SLG Slugging percentage The number of total bases divided by the total number of at-bats.
SO Strikeouts When a batter swings and misses or takes a third strike.
SV Saves Given to a relief pitcher when he is the last pitcher in a game won by his team and he is not the winning pitcher, and he pitches at least one complete inning and enters the game with no more than a three-run lead; or he enters the game with the potential tying run on base, at-bat or on deck; or he pitches at least three innings.
SVO Save opportunities The number of times a relief pitcher entered with the opportunity to earn a save.
TB Total bases The number of singles plus doubles times two plus the number of triples times three plus the number of home runs times four.
TC Total fielding Chances The number of putouts plus assists plus errors committed by a fielder.
TP Triple plays A defensive play in which three offensive players are put out as a result of one continuous action.
W Wins Credited to pitchers on wining teams.
WP Wild pitches Given to a pitcher when an errant pitch allows a runner or runners to advance.
1B Singles Batted balls that results in hitters reaching first base safely.
2B Doubles Batted balls that results in hitters reaching second base safely.
3B Triples Batted balls that result in hitters reaching third base safely.