The art of X-rays

It has been known for more that two hundred years that the photosensitive film produces images that we call photographs when exposed to light. These pictures result from the interaction between the photons, that are part of visible light, and a substance that surrounds film; hence the name photography. At the end of the 19th century, Roentgen discovered that X-rays could traverse opaque organic matter and that the difference in its densities would be captured by photographic film. These characteristics were immediately put to use by scientists in order to produce X-rays that have been used, almost exclusively, for medical purposes.