Metals are good conductors of electricity. In a metal some electrons are not held by one atom. These delocalised electrons are free to move through the whole structure.
When a metal is part of a circuit, the delocalised electrons carry electrical charge through the metal. This is why a metal conducts electricity well, both as a solid and when it is melted.
Metals are also good conductors of thermal energy. The delocalised electrons move through the metal and transfer energy from the hotter part to the cooler part. This is why a metal spoon in hot water quickly becomes hot all along its length.
