What is the principle of bakery?

The principal of the standard over is simply an enclosed space with enough density of the enclosure to hold heat at a steady temperature for a specific period of time to complete the cooking process. One of the best materials for this is brick or stone, though modern ovens get by with man-made insulation.

The principle of microwave oven is a simple one. Microwave ovens produce Electromagnetic waves called microwaves. These microwaves when fall on food containing water, the frequency of water matches with the frequency of the microwaves and thus the food stored inside is heated.