The main difference between an electric oven and a convection oven is the use of air. Convection ovens circulate the hot air while electric ovens simply heat the static air.
Convection ovens tend to be slightly more expensive than conventional electric ovens because the design is more complicated. Convection ovens include a fan built into the back of the unit. This fan is what causes the interior air to circulate, promoting quick and even heating.
In a convection oven, food requires less time to cook. Compared to an electric oven, the temperature of convection ovens can achieve the same results at a lower temperature. Conventional electric ovens often require rotating the food during the cooking cycle to compensate for uneven cooking. This additional step is not required in convection ovens. Another advantage of convection ovens is the capacity. Convection ovens can cook multiple items at the same time.
Convection ovens have a setting which turns on the interior fan. Not all types of foods benefit from circulating air. Generally, foods cooked in shallow pans benefit most from this setting. Items such as casseroles do not benefit from the air circulation. It is also best to avoid covering items with aluminum foil with the convection fan turned on.