X-ray = photograph of the inner part of your body, made with the use of X-radiation
X-radiation = rays that pass the soft tissue of your body, but are obstructed by blood and bones
Bones - white
Lung tissue- dark
Blood, muscles and organs - different shades between dark and light.
X-ray radiation is harmful when you are exposed to it for too long. Radiologists stand behind a lead screen to block the radiation.