Microwave radiation is used in microwave ovens to heat food. Microwaves have wavelengths between 1-30 cm and are absorbed by water, fats, and sugars in food. This causes the molecules in food to vibrate and produce heat through friction. Materials like glass, plastic, and ceramics are not affected as they do not absorb microwaves. A microwave oven uses a control unit and high voltage production unit to generate microwaves and heat food from the inside out simultaneously, cooking it faster than conventional ovens.