What does pitching out of the stretch mean?

Answer 1

When runners are on base, pitchers generally tend to pitch out of the stretch, meaning that they shorten the time it takes to prepare and throw a pitch. This is done to prevent base runners from stealing base. When there are no runners on base, pitchers tend to pitch out of the wind up.

Answer 2

Pitching from the stretch occurs when there are runners on base. When there are no runners on base the pitcher will use a full windup to throw the ball. In other words, once the pitcher starts the windup he does not stop before throwing the ball. But when there are runners on base, the pitcher will start a windup and then stop and look at the baserunners in an attempt to keep them close to the base before he throws. When the pitcher stops to look at the runners, this is called the stretch position.