The microwave oven was a by-product of a radar-related research project conducted around 1946 by Raytheon Corporation.

While performing tests on a magnetron tube Dr. Percy L. Spencer discovered that the candy bar in his pocket had melted. Intrigued (and not frightened?) he placed some popcorn kernels near the tube. The kernels exploded and popped all over his lab. The popcorn was followed by the egg, and from this simple experiment Spencer and Raytheon developed the microwave oven.

The first commercial microwave oven hit the market in 1947. They were enormous and expensive: weighing over 750 pounds (340 kg), and costing about $5000. At first, it was used exclusively in restaurants, railroad cars and ocean liners.

Other industries soon found the microwave heating quite advantageous. In time, microwaves were being used to dry cork, ceramics, paper, leather, tobacco, textiles, pencils, flowers.

In 1952, Tappan introduced the first home model at the very low price of just $1295.

By 1975 sales of microwave ovens exceeded that of gas ranges, and in 1976, the microwave oven became a more commonly owned kitchen appliance than the dishwasher, reaching nearly 60%, or about 52 million U.S. households.

There were many myths and fears surrounding these mysterious microwaves. However, more and more people were finding the benefits of microwave cooking to outweigh the possible risks, and microwave oven had developed from a luxury into a practical and time-saving appliance.

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