The appendicular skeleton is a part of the human skeleton that includes the bones of the limbs and the girdles that attach them to the axial skeleton. It consists of 126 bones, including those in the arms, legs, shoulders, and pelvis. The primary function of the appendicular skeleton is to facilitate movement and support the body's weight during activities such as walking, running, and lifting. The appendicular skeleton is divided into two main sections: the upper limb and the lower limb. The upper limb includes the bones of the humerus, radius, and ulna, while the lower limb consists of the femur, tibia, and fibula. The pectoral girdle connects the upper limbs to the axial skeleton, and the pelvic girdle connects the lower limbs, providing stability and mobility.