I have a strong feeling that I will not be alone with this choice - but no matter: This is my version. According to Wikipedia:
An X-ray (or Röntgen ray) is a form of electromagnetic radiation with a wavelength in the range of 10 to 0.01 nanometers, corresponding to frequencies in the range 30 petahertz to 30 exahertz (30×1015Hz to 30×1018Hz). They are longer than Gamma rays but shorter than UV rays. X-rays are primarily used for diagnostic radiography and crystallography. X-rays are a form of ionizing radiation and as such can be dangerous. In many languages it is called Röntgen radiation after one of the first investigators of the X-rays, Wilhelm Conrad Röntgen.Thus, in Norway X-rays are always called røntgenstråler and the pictures røntgenbilder. Ususally all this is shortened to rtg. Most people come into contact with X-ray when they are checked for broken bones or other medical defects, or when they are doing their dental check-ups. It is not as easy as one should imagine to diagnose correctly X-ray pictures, and as with all kinds of photography, many demands must be met to achieve the best possible result.I will show you an example of what a typical dental X-ray picture of a grown-up person looks like. The picture was taken in the mid 90s, so hopefully the situation for the same age group is better today.This is a so-called "bite-wing" - typical for routine examinations. I have not included all that one can read out of this (there would not be room), but have included some of the tissues and various dental restorative materials. The reason they look different is that they absorb different amounts of radiation, leading to less exposure of the film at this point. This is the basis for all X-ray diagnosis. A cavity would be totally black against the grey of the tooth-substance. However - you will not see this in this picture because the patient did not have caries! Nowadays, most x-ray pictures are digital, leading to both less exposure for patient and personnel, and less chemicals to the environment. A win-win situation.
PS For more about ABC Wednesday, please visit Mrs. Nesbitt's Place. It is well worth the effort.