Toasting bread what type of heat transfer

Heat is released.

Explanation:

In an exothermic reaction, the reactant(s) move into a more stable state when they form into the product(s). Thus, the excess energy is released in the form of heat.

Conversely, in an endothermic reaction, the reactant(s) move into a more unstable state. In doing so, energy is required for the chemical reaction to occur to force the reactant(s) into a less stable state. So, energy is absorbed to make the reaction occur.

Also, since energy was released, the net energy decreased. If energy was absorbed in an endothermic reaction, the net energy would increase.

Therefore, the answer is 'Heat is released'.