Conduction

Conduction requires two bodies at different temperatures to be in contact with each other for heat transfer.

Conduction takes place in substances such as solids where the molecules are closely packed. When the solid is heated, the molecules near the source of heat gain thermal energy and begin to vibrate faster.

The molecules that collide with the neighbouring cold molecules and transfer some heat energy. The neighbouring molecules now gain thermal energy and start vibrating rapidly.

The process continues until heat is spread throughout the solid and the entire solid attains a uniform temperature)

Definition

Conduction of heat is defined as the process of heat transfer through a substance without the displacement of molecules from their position.

Conductors

All the metals are good at transferring heat, they're called good conductors of heat.

Insulators

All such substances are bad at transferring heat, they're called bad conductors of heat or insulators.