Microwaves were invented in 1947, according to How Stuff Works. The first microwave was produced by Raytheon and was called the Radarange. It weighed 750 pounds, was 5 1/2 feet tall and cost $5,000.
Microwaves became available for home use in the early 1950s, but they were not very popular due to their size and cost. In 1967, a 100-volt countertop model was introduced with a price tag of less than $500. Although it was still pricey, it was smaller, safer and more reliable than previous models, and the microwave increased its popularity. By 1975, more microwaves than gas ranges were sold.