Copper is a good conductor of heat and electricity. It possesses high electrical and thermal conductivity. Due to the fact that virtually all valence electrons participate in conduction. It is second to elemental silver in conductivity and very economical which is why Cu is preferred for wiring purposes.
Heat transfers from warmer to cooler things. Heat seeks its own level like water or pressure, and equalizes everywhere. If several objects with different temperatures are in contact, those that are warm become cooler and those that are cool become warmer. They tend to reach a common temperature. This equalizing of temperature occurs in three ways: conduction, convection, and radiation. Conduction usually takes place in solids, convection in liquids and gases, and no medium is required for radiation.
Conduction: If you leave the end of a metal poker in a fire for enough time, its handle will get hot. Energy is transferred from the fire to the handle by (thermal) conduction along the length of the poker. The vibration amplitudes of the atoms and electrons of the metal at the fire end of the poker become relatively large because of the high temperature of their environment. These increased vibrational amplitudes, and thus the associated energy, are passed along the poker, from atom to atom, during collisions between adjacent atoms. In this way, a region of rising temperature extends itself along the poker to the handle. Heat conduction occurs by electron and atomic collisions.
Metals are better conductors than non-metals. This is because metals have the "loosest" outer electrons, which are free to carry energy by collisions throughout the metal. They are excellent conductors of heat and electricity for this reason. Silver is the best conductor (but costly too!). Copper is next best followed by the common metals aluminium and iron. Wool, wood, straw, paper, cork, and Styrofoam, on the other hand, are poor conductors of heat. The outer electrons in the atoms of these materials are firmly attached. Poor conductors are called insulators.