A convection oven is any oven that has a fan in it. A fan assisted oven is an oven with heating elements in the oven (top and/or bottom) and a fan at the back. These can be either electric or gas ovens. Usually a fan assisted oven will have the option of cooking with the fan switched on or off. Unlike conventional radiant (also called thermal) ovens, convection ovens have a fan that continuously circulates air through the oven cavity. When hot air is blowing onto food, as opposed to merely surrounding it, the food tends to cook more quickly.