X-ray

                                                                                 X-ray

X-rays are electromagnetic waves produced by a machine that aims to be able to see the inside of our body, thanks to this invention, fractures of some bone can be seen but it also has other uses such as chest radiographs that detect pneumonia or mammography to detect breast cancer 

Next there is a paragraph where it speaks more specific that are x-rays:

X-rays are a type of radiation called electromagnetic waves. X-ray images show the inside of your body in different shades of black and white. This is because different tissues absorb different amounts of radiation. Calcium in the bones absorbs most of the X-rays, making the bones appear white. Fat and other soft tissues absorb less, and they appear gray in color. The air absorbs the least amount, so the lungs look black.

if wihelm hadn´t  discovered X-ray i wouldn´t have healed my arm 

if i had dicovered X-ray i would have used in another way

if I had broken my arm I would have used x-rays to know the damage

if x-rays hadn't worked the world would have looked for another invention

if x-rays hadn´t  damaged the skin the world wouldn´t have looked for a suit to protect it

penicillion