Microwave ovens for residential cooking have changed greatly since the early 1970's, when they began to be common in homes. Options have increased and prices have decreased. In the 1980's, the number of microwave oven owners surpassed the number of dishwasher owners.
A countertop microwave is a stand-alone kitchen appliance that sits on top of a kitchen counter. A built-in microwave is mounted to a cupboard or wall. Both models come in a wide variety of sizes, power capacities and colors.
Dr. Percy LaBaron Spencer invented the microwave oven for cooking food around 1946. Dr. Spencer did not complete high school, but was a self-taught engineer and eventually held 150 patents.
The first patent for a microwave oven that cooked food was filed in 1946. The first microwave was sold commercially the next year to a restaurant. It was 5.5 feet tall, weighed 750 pounds and cost $5,000.
Countertop microwaves are generally less expensive than built-in microwaves. Countertop models require no special installation and are simple to replace. These models are easy to pack, store and move when relocating.
Built-in microwaves free up counter space in the kitchen. Smaller built-in microwaves require a frame mounted to a wall or cupboard for support. Larger microwaves often cannot be built in because of their weight. Built-in microwaves may require additional construction work to ensure ventilation.