X-ray waves are actually very capable of passing through most objects. They can very easily pass through human bodies, which is why they are so useful in medicine.
Shining an X-ray through the body makes X-ray pictures. The X-ray then passes through some tissues and it turns the film black, which leaves white shadows on the film. X-rays pass through types of tissue differently. Since bones contain calcium and are dense, they show up white on film because they block X-rays. Skin, fat, muscle and blood let X-rays through and show up black on film. Although X-rays can be very helpful, the radiation is very dangerous if used in high doses, this is why the beam is inside lead. This is the reason why when you take an X-ray every body part except for the affected one is covered. Also this is why the radiographer, the person who takes your X-ray, has to stand behind a wall while the picture is being taken. X-rays are also used in airports to see inside of your luggage. X-rays are also used by astronomers because many objects in the universe emit