12 Inventions You Won't Believe Came From War

Microwave Ovens

As researchers worked to improve radar (yet another war-time advancement) during WWII, they had to invent a whole range of other devices. One of them was the cavity magnetron, built by a British team in the late 1930s. A few years later, in 1945, an American tinkerer named Percy Spencer was working with a radar machine based on these war-time developments that emitted microwaves. When he realized the microwaves had melted the candy bar in his pocket, he began to experiment with how to heat food on purpose with microwaves. His first success – and clearly the most pivotal one – was popping popcorn.