Together, muscles and bones comprise what is called the musculoskeletal system of the body. The bones provide posture and structural support for the body and the muscles provide the body with the ability to move (by contracting, and thus generating tension). The musculoskeletal system also provides protection for the body's internal organs. In order to serve their function, bones must be joined together by something. The point where bones connect to one another is called a joint, and this connection is made mostly by ligaments (along with the help of muscles). Muscles are attached to the bone by tendons. Bones, tendons, and ligaments do not possess the ability (as muscles do) to make your body move. Muscles are very unique in this respect.