Who invented the microwwave oven?

Percy Spencer. On October 8, 1945, Raytheon filed a US patent for Spencer's microwave cooking-process, and an oven that heated food using microwave energy from a magnetron was soon placed in a Boston restaurant for testing.

The first time the public was able to use a microwave oven was in January 1947, when the Speedy Weeny vending machine was placed in Grand Central Terminal to dispense "sizzling delicious" hot dogs.
Percy Spencer. On October 8, 1945, Raytheon filed a US patent for Spencer's microwave cooking-process, and an oven that heated food using microwave energy from a magnetron was soon placed in a Boston restaurant for testing.

The first time the public was able to use a microwave oven was in January 1947, when the Speedy Weeny vending machine was placed in Grand Central Terminal to dispense "sizzling delicious" hot dogs.