Perfect thermal contact

Perfect thermal contact means when two things are touching each other, they don't have any air or anything else between them. This means that heat can travel really easily between the two things, which can make it so that things with perfect thermal contact are at the same temperature. Imagine two pieces of metal that are touching each other. Heat from the one piece of metal can spread to the other piece of metal really quickly, which makes them the same temperature. That's perfect thermal contact!