The lats or latissimus dorsi start just below the outer and upper back regions. They span the length of the torso down to the lower back. The lats, while defined as a single muscle, can be location targeted (meaning outer lats, lower lats, middle lats) through various lat exercises, grip locations, and body position modifications.
Targeting of the lats is highly desirable by many weight lifters. Through proper training and form adjustment, they can provide one with a V-taper appearance.