How does a microwave heat food so quickly?

Microwaves heat food quickly by using electromagnetic radiation at a frequency of about 2.45 gigahertz, which causes water molecules in food to vibrate rapidly. Water molecules are polar, meaning they have positive and negative ends, and they constantly try to align themselves with the alternating electric field of the microwave radiation, flipping back and forth billions of times per second. This rapid molecular movement generates heat through friction throughout the food simultaneously, rather than relying on heat slowly conducting inward from the surface like a conventional oven. Because the microwaves penetrate several centimeters into the food and heat it from within all at once, the process is dramatically faster than traditional cooking methods.