Energy always flows from higher to lower temperatures according to the second law of thermodynamics meaning that a material with higher temperature is more likely to transfer its energy to an adjacent material with lower temperature (Tritt, 2006, p.6).
On the other hand, convection makes material such as air and other gases bad conductors of heat hence it has to be maintained to prevent unnecessary changes. Apart from that, thermal conductivity has been recorded to track electrical conductivity since heat energy is also transferred during the transfer of electric currents across materials.
A material that has higher thermal conductivity is referred to as a good conductor of heat while a material that has lower thermal conductivity is referred to as a poor conductor of heat. For example copper is a good conductor of heat due to its physical properties while wood is a poor conductor of heat.
Many processes rely on the knowledge of thermal conductivity especially in the manufacturing and processing industries. This is to ensure that the correct materials are used in making product that are used by humans. For instance, materials that have high thermal conductivity are mostly used to application that heat sink such as heaters while those material that are poor thermal conductors are commonly used as heat insulators to prevent heat loss.