The human skeleton — our internal framework that includes bones and cartilage — evolved over millions of years. It comprises an axial skeleton, which consists of the skull and the spine, as well as an appendicular skeleton, which includes the shoulders, hips, arms and legs.
One of the main functions of the skeleton is to protect our squishy internal organs, but another important function is to help us move; bones act as levers with the assistance of muscles, tendons and ligaments.
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