Microwaves are electromagnetic radiation used in radar and microwave ovens.
Microwaves occupy the portion of the electromagnetic spectrum between radio waves and infrared radiation. The term covers a broad range of wavelengths, commonly described as roughly one metre to one millimetre, though boundaries vary by convention. Radar systems use microwave reflections to determine the range, direction, or speed of objects.
Microwave ovens heat food mainly by creating an alternating electric field that makes polar molecules, especially water, rotate and dissipate energy as heat. The oven’s metal enclosure helps keep the radiation inside, while a magnetron traditionally generates the microwave energy.
Microwaves are non-ionizing radiation: individual microwave photons do not normally have enough energy to ionize atoms. Their main biological effect at sufficiently high power is heating, which differs from the chemical damage associated with ionizing radiation such as X-rays.