What is a "microwave oven"?

A microwave oven is a kitchen appliance used for cooking, heating, and defrosting food by using microwave radiation to excite water molecules in the food, causing them to vibrate and generate heat. It typically consists of a chamber surrounded by a metal casing, a control panel for setting cooking times and power levels, and a glass or plastic door with a mesh screen to allow viewing of the food while preventing microwave leakage. To use a microwave oven, food is placed on a microwave-safe dish or container and positioned in the center of the cavity. The desired cooking time and power level are then selected on the control panel, and the microwave oven is activated.