Which joint type is described as immovable, such as those between the bones of the skull?

The joint type described as immovable, particularly those found between the bones of the skull, is a suture joint. Sutures are fibrous joints that connect the flat bones of the skull. They are characterized by their tightly stitched or interlocking nature, which helps protect the brain by providing a rigid structure that does not allow for movement. As a result, sutures effectively stabilize the skull while allowing for growth during childhood and early development.

In contrast, ball and socket joints allow for a wide range of movement in multiple directions but are not immovable; they enable significant mobility, found in joints like the shoulder and hip. Hinge joints allow for movement in one plane, similar to a door opening and closing; these are seen in the elbows and knees. Pivot joints allow for rotational movement, like the turning of the head, which also involves movement rather than being immovable. Thus, the unique characteristics of suture joints make them distinct from other types of joints in the body.