An X-ray, rarely called X-radiation, is a penetrating form of high-energy electromagnetic radiation. Most X-rays have a wavelength ranging from 10 picometers to 10 nanometers, corresponding to frequencies in the range 30 petahertz to 30 exahertz (30×1015 Hz to 30×1018 Hz) and energies in the range 124 eV to 124 keV. X-ray wavelengths are shorter than those of UV rays and typically longer than those of gamma rays. In many languages, X-radiation is referred to as Röntgen radiation, after the German scientist Wilhelm Conrad Röntgen, who discovered it on November 8, 1895. He named it X-radiation to signify an unknown type of radiation. Spellings of X-ray(s) in English include the variants x-ray(s), xray(s), and X ray(s).

X ray printable coloring pages, Not only can they learn about the assorted colorings, this also helps them learn about the ways in which they migrate around various parts of the world, and it helps improve their memories with different memory games that can be played once the various pages are colored.