Masonry oven India, tandoors are traditional clay ovens, although these days modern electrically fired tandoors are available. The open-topped tandoor is a transitional design between the earth oven and the Roman-plan masonry oven. In the precolumbian Americas, similar ovens were often made of clay or adobe and are now referred to by the Spanish term "horno" (meaning "oven"). Horns are also traditional in the American Southwest. The traditional direct-fired masonry design is often called a "Roman" or "black" oven and dates in Western culture to at least the Roman Republic. It is known as a black oven because the fire generates soot
Convection oven heating element which increases the oven's ability to cook foods evenly. Another form of a convection oven is called an "impingement oven". This type of oven is often used to cook pizzas in restaurants. Impingement ovens have a high flow rate of hot air from both above and below the food. The air flow is directed onto food that usually passes through the oven on a conveyor belt. Impingement ovens can achieve a much higher heat transfer than a conventional oven. There are also convection microwave ovens which combine a convection oven with a microwave oven to cook food with