We are composed of one skeleton that can be divided into two major regions, the axial and appendicular skeleton. The axial skeleton makes up our central axis and consists of the following bones: skull, vertebrae, ribs and sternum.
The appendicular skeleton consists of the limbs and girdles. The girdles are the attachment points for the limbs. The pelvic girdle is the attachment point for our thigh bone (femur) and consists of an individual os coxae (ilium, icshium, pubis). The pectoral girdle is formed by the clavicle and scapula and serves as the attachment point for our are (humerus).
Source: Mind of Aaron
This video goes over the differences between the axial and appendicular skeleton
Source: Self made