CT scans (or Computed Tomography), MRI (Magnetic Resonance Imaging) scans, and X-rays all use different methods to produce images from inside the body. CT scans take a large number of X-ray images while moving around the body and a computer compiles them into a set of pictures for the doctor. MRI scans use powerful magnetic fields and radio waves to create a 3-D image. X-rays use radiation to produce a single image like a photograph. These different imaging methods are used in different ways.,