If you think only Superman has X-ray vision, think again. Your doctor has it too! Okay, so your doctor needs a machine to take X-rays, but it's still pretty cool.
X-rays are special pictures that show the inside of the body. It's just like having a regular photo taken. Sit still, click and it's done. You don't feel a thing.
Your doctor may take a single X-ray of your left wrist, hand and fingers. This can then be used to estimate how well your overall skeleton is developing, compared with other children of your age.