In the human body, a joint is a juncture where two or more bones come into contact. Joints can take on numerous forms, ranging from those fixed in place such as skull sutures, to those that provide a wide range of mobility like the hip, knee, and shoulder. The way bones in the joint are connected to one another also takes on a variety of forms, each determining the level of mobility associated with the joint. Fibrous joints permit no mobility, strictly connecting two adjoining bones. Amphiarthrosis joints such as vertebrae act as shock absorbers and are mostly made from cartilage.

Finally, synovial joints permit a variety of movements. They are distinguished from other types of joints by their capsules that surround the articulating surfaces of the joint that contain synovial fluid. Hips, knees, and shoulders are all examples of synovial joints.