The correct answer is "Microwave Ovens".
The commercial Microwave Oven was invented by American engineer Percy Spencer during the immediate years after the Second World War. Based on radar technology, he introduced the first microwave oven concept named "Radarange" in 1946. Afterward, the American company named "Raytheon" would license its patents in 1955, laying the path to further improvements and mass production of the products in the next decade.