What did you notice about the outside surface of the mug when touch it?

Question: What did you notice about the outside surface of the mug when touch it?

This transfer of heat occurs from the hot coffee and hot mug to the surrounding air. The fact that the coffee lowers its temperature. The hot coffee heats the paper cup by conduction. The cup provides little insulation so many coffee shops provide a cardboard insulator to protect your fingers from getting burned.