COMMISSIONED OFFICER. Commissioned Officers are the managers, problem solvers, key influencers and planners who lead Enlisted Soldiers in all situations. Enlisted Soldiers perform specific job functions and have the knowledge that ensures the success of their unit's current mission within the Army.
The primary difference between chin-ups and pull-ups is that chin-ups are done with a supinated grip, palms facing in toward the exerciser. This sets up the mechanics so that chin-ups, while still primarily a back exercise, also provide a good arm workout, particularly for the biceps.
The thing that differentiates a pull up from a chin up is the hand grip used, they are both excellent compound exercises, meaning they work multiple muscles, specifically the muscles in your back, shoulders and arms, but because of this change in grip the focus of primary effort changes from one muscles area to another.