Final answer:
The electromagnetic spectrum includes various types of radiation such as visible light, UV, and X-rays, with the sun and stars being natural sources of this radiation.
Step-by-step explanation:
The electromagnetic spectrum is a term used to describe the entire range of electromagnetic radiation which encompasses the various types of radiation including radio waves, microwaves, infrared (IR), visible light, ultraviolet (UV), X-rays, and gamma-rays. The natural source of many of these types of radiation, particularly visible light, UV, and X-rays, is the sun. Additionally, other astronomical objects like stars also emit various forms of electromagnetic radiation, which are all parts of the electromagnetic spectrum.