Toasting in a toaster is usually considered cooking by (infra red) radiation. But the hot coils touch the toast so an element of heating by conduction occurs as well. Are they both equally as valid or is one more valid than the other. If the latter than which one and by how much? On the other hand, if you cook a bread on top of a flame, would it be considered convection heating, radiation heating or conduction heating. I know that if you heat a saucepan over a flame it is considered heating by conduction. So if you replace the saucepan by a piece of bread does it change?