편평골, or "Flat Bone," refers to a type of bone in the human body that is characterized by its thin, flattened shape. These bones serve various functions, including providing protection to vital organs and serving as attachment points for muscles. Examples of flat bones include the skull, sternum, and scapula. Flat bones are primarily composed of two layers of compact bone surrounding a layer of spongy bone, which helps reduce weight while maintaining strength. They play a crucial role in the body's structure and support, contributing to the overall framework that protects the brain and other important organs.