Radiation is defined as the emission or transmission of energy in the form of waves or particles through space or a medium. It can be ionizing or non-ionizing depending on its energy level, with ionizing radiation having enough energy to break chemical bonds. Examples of different types of radiation include ultraviolet light, heat, visible light, x-rays, alpha particles, sound waves, microwaves, and electromagnetic radiation from cell phones. An experiment is described where a magnifying glass is used to concentrate sunlight and ignite tissue paper, demonstrating how radiation can transfer energy.