The document discusses different types of bone fractures. It defines a simple fracture as a closed fracture with no open skin wound that is typically treated with immobilization in a cast. A greenstick fracture is described as an incomplete break where one side of the bone is broken and the other is bent, commonly found in children. An impact fracture involves bone fragments being pushed into each other. A compound or open fracture is defined as when the skin is broken through from the fracture, usually requiring surgical treatment.