At Bat
Plate appearances minus the ones that are not the hitter's fault or choice: walks, HBP, sacrifices.
What it actually is. A plate appearance that ended with the bat deciding it: a hit or an out in play or a strikeout. Walks, hit by pitches and sacrifices are stripped out.
What a scout reads off it. At bats exist to be a denominator for average and slugging, and the exclusions are what make them a slightly dishonest one. A hitter who walks eighty times has eighty fewer at bats than his teammate for doing something good.
How it lies to you. A sacrifice fly is not an at bat but is an out, which means a hitter can make an out and have his batting average go up. That is a genuine oddity of the rulebook and not a bug in the arithmetic.
Batter's Eye: look up anything in baseball