The axilla, commonly known as the armpit, is the area located beneath the shoulder joint. It serves as a passageway for nerves, blood vessels, and lymphatics that travel between the upper limb and the thorax. The axilla is bordered by muscles, including the pectoralis major in the front and the latissimus dorsi at the back. This region plays a crucial role in the body's lymphatic system, housing lymph nodes that help filter harmful substances. The axilla also contains sweat glands, which contribute to body temperature regulation. Overall, it is an important anatomical area for both movement and immune function.