Plans for the first microwave were patented on Oct. 8, 1945, but the microwave itself was not actually created until 1947. A man named Percy Spencer came up with the idea for the invention, but his employer, Raytheon, officially filed the patent request.
While Spencer was working on a microwave-emitting radar set during one of his shifts at Raytheon, he realized that the candy bar in his pocket was melting. After some trial and error, he discovered that microwaves could effectively heat food. Spencer went on to create the world's first microwave oven, which was patented by Raytheon. Spencer himself received no royalties for his invention beyond a $2 reward from his corporate bosses.
The first food prepared in Spencer's microwave was popcorn, a microwaveable snack that is still popular today.