Conduction is the flow of heat energy from a region of high temperature to a region of low temperature without overall movement of the material itself.
Conduction occurs mainly in solids – most liquids are really poor conductors and hardly any conduction occurs in gases.
A poor conductor of heat is called an insulator.
Metals are good conductors of heat.
Higher tier only: Metals are good conductors because they contain free electrons.
Trapped air is a very good natural insulator.
Hair, fur, feathers and wool are good insulators because they trap air.
