They have a relatively large surface area and they are relatively flat, relatively thin. Now let's move on to our irregular bone. So basically, these are the bones that have a certain unique shape that we cannot actually label as long bones, short bones, or flat bones. So these bones have unique shapes that help them carry out certain types of unique function. So typically, our irregular bones consist of bull compact as well as spongy bones. So they have spongy bone at the center and compact bone, usually on the surface.