Oven is a device for baking cooked foods by forming hot air, generally in a closed or semi-closed configuration. Ovens, also known as ovens, ovens, and ovens, are called barbecues when heated in open form with hot air. Ovens can also be used to refer to devices that process at high temperatures with hot gases. Traditional ovens use wood and coal to heat them. Modern ovens are multi-functional, using electric or natural gas respectively. The ovens are divided into single-layer, double-layer and three-layer types. Each layer is independently controlled and can be used at the same time. It can also be used in single-layer single-layer ovens. And three-layer type, each layer is independently controlled, generally has an automatic constant temperature system.