The best oven toaster griller converts electrical energy into heat to bake food. The fan circulates the heat evenly. The cooking process is relatively slow.
A microwave makes use of microwaves to heat the food. The cooking process is quicker.
Some may assume that the oven toaster is only meant to toast bread, but it can actually do so much more. There are instances when you can use the oven toaster for baking a few goodies but usually in small batches because the toaster oven is small. The convection oven is known to be much bigger, and it can bake and cook more efficiently as compared to the toaster. Another difference between the two is the price.
You can purchase a great toaster oven for less than the price of a very basic convection oven. Convection ovens are also known to have the ability to cook food more evenly. This is because it has huge fans inside the oven that will help keep the heat stable.