Being able to see inside the body makes diagnosing internal conditions much easier and more accurate. The many body scans doctors can do include X-rays, CT scans, MRIs, ultrasounds, and PET scans. All these letters stand for something. Readers of this understandable narrative will find out exactly what those abbreviations are and how and why each scan is performed. Curious readers will be fascinated by real images from these different kinds of scans and by illustrations that help explain complicated concepts, such as the electromagnetic spectrum.