Countertop microwave ovens are compact kitchen appliances designed for heating and cooking food quickly using microwave radiation. They are typically placed on kitchen countertops and come in various sizes and power levels, making them suitable for different cooking needs. Most models feature easy-to-use controls and preset cooking options for common tasks like defrosting, reheating, and popcorn preparation. These ovens work by agitating water molecules in food, generating heat that cooks the food from the inside out. Countertop microwave ovens are popular for their convenience and efficiency, allowing users to save time in meal preparation compared to traditional cooking methods.