The first microwave oven was invented in 1945 by Percy Spencer, a self-taught engineer working for the Raytheon Corporation. Spencer noticed that microwaves could heat food quickly when he was experimenting with radar equipment. He patented his invention in 1947, and the first commercial microwave oven was introduced in 1947.
However, early microwave ovens were very expensive and were mainly used in commercial kitchens. It was not until the 1960s that microwave ovens became affordable for home use. In 1967, the Amana Corporation introduced the first countertop microwave oven, the Radarange. The Radarange was a success, and microwave ovens quickly became a common appliance in American homes.