An X-ray is a common quick, painless imaging test that produces images of the structures inside your body used to diagnose, monitor, and treat many medical conditions.

X-rays use small amounts of radiation to create images of your body. The level of radiation exposure is considered safe for most adults, but not for a developing baby. If you’re pregnant or believe you could be pregnant, tell your doctor before you have an X-ray. 

X-ray beams pass through your body, and they are absorbed in different amounts depending on the density of the material they pass through. Dense materials, such as bone and metal, appear white on X-rays. The air in the lungs shows up as black. Fat and muscle appear as shades of gray.