Diagnostic radiology involves the use of X-rays to see inside the human body. An image is produced by allowing a small amount of radiation to pass through the body which is then recorded on photographic film or by a digital detector. Different parts of the body will absorb x-rays in varying degrees. Bone absorbs much of the radiation while soft tissue allows more of the x-rays to pass through. As a result, bones will appears white on the x-ray while soft tissue will vary with different shades of gray. Examples of such examinations include x-rays of the chest, abdomen, pelvis, and extremities.