The word 'radiation' has to do with energy or matter moving through space. There are many forms of radiation that astronomers and physicists know about. Sunlight is a form of electromagnetic radiation produced by the sun, but so is ultraviolet radiation, infrared radiation and gamma radiation. Any heated body produces electromagnetic radiation.
We also use the term 'radiation' to describe fast-moving particles of matter. One form of these found in space is cosmic radiation or more commonly 'cosmic rays'. They are not made of light energy, but are actually the nuclei of atoms such as hydrogen, helium, iron and others, which travel through space at hundreds of thousands of kilometers per second. Some electrons in the cosmic rays travel at nearly the speed of light.
An even more exotic form of radiation that is not made of light or matter, is neutrino radiation. Neutrinos are particles that travel at the speed of light just like electromagnetic radiation, but they are not made of matter and are also not produced by electric or magnetic fields. Any body that is hot enough to fuse hydrogen into helium such as the center of our Sun, is also producing neutrino particles too. These particles slip right past ordinary matter and can escape from the core of the sun in only a few seconds. Billions of these neutrino particles are flowing through your body every second! Like other forms of radiation, they carry energy away from the place where they were created. When they are absorbed, they deliver this energy to the body that absorbs them.