In order for your shot to reach its intended location on a target, a shooter must have sight picture and alignment. Sight alignment is the symmetry between the front sight and rear sight. Your front sight should be in the exact center of the rear sight, at the same height of the rear sight. Remember the old adage: equal light, equal height.
Sight picture is what you see when you look at your target. It includes your sights and target. You must focus your eyes on the front sight of your pistol; the target and rear sight should be blurry.