Joint

300px|thumb|right|a typical joint

A joint is the place where two or more bones make contact. They allow movement (except for skull bones) and give mechanical support.

Joints have cartilage in between them, which help to make the movement flexible. Joints are described structurally and functionally. Structural classification is how the bones connect to each other; function is the degree of movement between the articulating bones. 

 Synovial bursa 
A synovial bursa is a small fluid-filled sac lined by a synovial membrane. It has an inner capillary layer of viscous synovial fluid (bit like raw egg white). The bursa is a cushion between bones and tendons and/or muscles around a joint. This helps to reduce friction between the bones and allows free movement.

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