American engineer Percy Spencer invented the modern microwave oven from radar technology developed during WWII. Named “Radarange,” the oven went on sale in 1946.

A microwave oven introduced by Tappan in 1955 was too large and expensive for general home use.

The first microwave oven with a turntable was produced by the Sharp Corporation in 1964.

In 1967 the Amana Corporation introduced a countertop microwave oven.

Affordable microwave ovens became available for residential use in the late 1970s.

Source: Wikipedia