There’s no such thing as a straight line. Zoom in close enough to anything and you’ll spot irregularities. Even a laser light beam is slightly curved.
100 Mind-Blowing Beam Facts
The microwave oven was another accidental invention. The heating effect of a high-power microwave beam was accidentally discovered when it melted a chocolate bar in 1945. Percy Spencer, an American self-taught engineer, was working on an active radar set when he noticed his chocolate melted in his pocket.