* Metals: Metals have free electrons that can easily move throughout their structure. This allows for the flow of electrical current with minimal resistance.

* Plastic: Plastics are insulators. Their electrons are tightly bound to their atoms and don't move freely. This makes them poor conductors of electricity.

* Wood: Wood is generally a poor conductor of electricity. While it might conduct a small amount, it's not nearly as efficient as metals.

In short: Metals are the best electrical conductors, followed by wood, and then plastics.