[CBeisbol]

It's all in the manual

All players have a set of three basic batting ratings: Stuff, Movement, and Control. Each of these has a matching potential rating.

Stuff
Stuff is a measure of the quality of a pitcher's pitch repertoire. Think of it as essentially how a pitcher "puts it all together." Stuff directly affects the number of strikeouts a pitcher throws.

Movement
Movement is a measure of the movement on a pitcher's pitches. It is harder for batters to make good contact with pitches that have good movement. As a result, pitchers with high Movement ratings tend to give up fewer home runs.

Control
Control is a measure of a pitcher's accuracy. Pitchers with good Control ratings tend to walk fewer batters.

https://manuals.ootpdevelopments.com...tching_ratings