X-Ray or radiography uses a very small dose of ionizing radiation to produce pictures of the body's internal structures. X-Rays are the oldest and most frequently used form of medical imaging. They are often used to help diagnosed fractured bones, look for injury or infection and to locate foreign objects in soft tissue. A X-ray is a type of electromagnetic radiation, like visible light. X-ray equipment sends individual X-ray particles through the body and records the images on a computer or on film. Bones, metal and other dense structures block most of these particles and appear white on an X-ray image. Structures that contain air will appear black on the image, while fat, muscle and fluid will appear in shades of grey.