When Percy Spencer was doing radar work for Raytheon, he figured out that microwave radiation could melt chocolate. After several experiments, Spencer created the world's first microwave oven. Not surprisingly, the first food cooked in this oven was popcorn. Although this happened during the 1940s, microwaves would not become a household standard for nearly 40 years. The first commercial microwave oven was over six feet tall.

Defense contractors were among the first companies to commercially manufacture microwave ovens--it was these contractors who were most familiar with the magnetrons needed to produce microwave radiation. When microprocessor prices fell in the late 1970s, microwaves could be built using electronic controls, making them much easier to use. The leap from industrial kitchens to household countertops was a short one.

Microwave Ovens Are among the Most Popular Kitchen Appliances
Naturally, the most popular kitchen appliances are the oven and refrigerator, but microwave ovens are a close third. Most estimates indicate that over 90 percent of all American households own a microwave. Older microwaves brought concerns with uneven cooking, but modern microwaves are great for killing bacteria. In fact, even older microwaves can kill all of the bacteria in food--just make sure to heat food until it is hot, and to let it stand for several minutes after cooking.

From a professional chef's point of view, there are several advantages to microwave ovens, but only in certain situations. Microwave ovens are preferable for melting fats and chocolate. Also, microwaves are usually better for cooking grains, such as oatmeal, and thawing meats and veggies. However, be careful when using a microwave to boil water--when the hot water is disturbed, it can boil over, causing damage and hand burns.