From BasketballWiki







The Jab Step is a move that can be made while in triple threat position allowing you to create space or unbalance a defender in anticipation of taking a shot, attacking the rim off the dribble, or creating a passive lane. Once a pivot foot has been set, you use the non-pivot foot to quickly step towards the defender without picking up the pivot foot. The threat of going to the rim often forces the defender to retreat a step or adjust their balance enough for the offensive player to make a move to the rim or use open space to make a shot attempt.

Breakdown of the Carmelo Jab Step courtesy of ShotMechanics.com