X-rays are a type of radiation called electromagnetic waves. X-ray imaging creates pictures of the inside of your body.
An X-ray, or, much less commonly, X-radiation, is a penetrating form of high-energy electromagnertic 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.
X-rays are part of the electromagnetic spectrum, with wavelengths shorter than UV light. Different applications use different parts of the X-ray spectrum.
X-ray image of human lungs