Cartilaginous, or slightly movable joints, have a cushion of cartilage in between the bones, with the bones resting on these beds of cartilage. This cushion of cartilage stops the bones from rubbing together.
As the name suggests, these joints are slightly moveable, with ligaments or cartilage stopping them from moving too far.
Joints are classified as either fibrous or cartilaginous, with one type of each considered slightly movable.
Fibrous joints with a limited range of motion (ROM) are known as a syndesmosis. In a syndesmosis joint, the bones are separated by a substantial space and united by fibrous connective tissue.
Cartilaginous joints with a limited ROM are known as a symphysis. In a symphysis joint, the bony surfaces are united by fibrocartilage.
These types of joint are structures that hold the skeletal frame together, providing rigidity, but at the same time allowing a small amount of movement.
An example of this type of joint is thus the joint between two vertebrae a small amount of movement is permitted, and indeed necessary between the bones, but excessive movement would cause damage to a critical area of the body (the spinal chord).