If its temperature has lowered, its internal energy has lowered as well. Heat is likely to exchange between matter. This process of exchanging heat is called heat transfer. Each is as important as the next. Conduction deals with the transfer of heat in matter in its solid state.
Molecules then collide and heat it up when they pass objects.
Heat can also be transferred within the same object. This process is known as thermal conductivity. Objects with a high level of thermal conductivity are usually good conductors of electricity. One good example is gold. Objects with a low level of thermal conductivity are usually nonconductors.