Conduction

Conduction is heat passing through a material from particle to particle, without the material itself moving. The particles at the hot end move faster and jostle their neighbours, which then jostle theirs, so the heat creeps along. It is how the handle of a metal spoon in hot tea gets warm. Metals are good conductors, copper among the best; wood, plastic, wool and above all still air are poor conductors, or insulators, which is why pan handles are wooden and warm clothes trap air.