X-rays are electromagnetic radiation that deferentially penetrates structures within the body and creates images of these structures on photographic film or a fluorescent screen. These images are called diagnostic X-rays.
X-ray exams are used for many purposes, including determining if a bone is broken, seeing whether an internal organ is infected, and looking for cancer. There are many different types of X-rays currently used to detect cancer. For example, the barium enema (a series of bowel X-rays with contrast medium), are routine procedures sometimes used for cancer screening in adults of certain age groups.