The Jab
The Jab is one of the four main punches in Boxing, and is the most important punch in a Boxer's arsenal. The Jab sets up all the other punches and keeps your opponent off balance. The Jab is a quick straight punch, thrown with the lead hand from the guard position (hands by the face).
The Boxer must bend his knees slightly and keep his chin down as he throws the Jab. The Jab is thrown with a small clockwise rotation of the torso and hips, while the fist rotates 90 degrees, becoming horizontal upon impact. As the punch reaches full extension, the lead shoulder can be brought up to protect the chin from a counter punch.
After making contact with the target, the lead hand is retracted quickly to return to the guard position in front of the face. The Jab is the most important punch in Boxing, because of its speed and it provides a good amount of protection from a counter punch. A Boxer with a good Jab, can use it to dictate the pace of a fight.
The Jab has the longest reach of any punch and does not leave the fighter off balance. It can wear an opponent down and can keep an opponent at a distance from you. The Jab is not a power punch, but is used to set up power punches. There is a saying in Boxing, "lead with speed, follow with power."
The Jab can be used as a probing punch to gauge distance and to find an opening in your opponent's defense. For added power a short step with the lead foot towards your target as the punch is thrown; this puts the entire body behind the punch.