There are totally 206 pieces of bones in an adult human body. The pieces can be divided into 2 categories by their positions: axial skeleton and appendicular skeleton.
- Axial skeleton is composed of skull, spine, ribs and sternum(mainly our bones in the center).
- Appendicular skeleton is composed of upper extremities(our two arms) and lower extremities(our two legs).
Though generally mankind has 206 pieces of bones, some individuals may have different numbers. An investigation in 1985 showed that some of the Chinese had only 204 bones, 2 pieces less than people in western countries. The reason to this was that there were only 2 pieces of bones on their fifth metatarsal, and 3 pieces on western people. 1 piece less on each foot, which made the Chinese having 204 pieces of bones in total.