The main role of cartilage in the human body is to provide support and flexibility to various structures. This specialized connective tissue is found in joints, the rib cage, ear, nose, and trachea, where it serves multiple functions. Cartilage acts as a cushion in joints, absorbing shock and reducing friction between bones during movement. It also maintains the shape of certain body parts, such as the ear and nose, and aids in the structural integrity of the respiratory system. Additionally, cartilage plays a critical role during embryonic development.