All materials do not allow electricity to pass through them. Materials that allow electricity to pass through them are called conductors. Conductors conduct electric current. Since metals are good conductors of electricity, electric wires are made of metals. These electric wires act as conducting materials. So they are used to make electrical circuits. Some common conductors that conduct electric current are copper, silver, gold and aluminium. Copper is the most popular material used for wires. Sometimes we receive electric shocks because our bodies are also good conductors of electricity.
Materials that do not allow electricity to pass through them are called insulators. Insulators oppose electric current and so they are used as protection from the dangerous effects of electricity. Some common insulators are glass, air, plastic, cotton, thermocol, wood and rubber.
Water is a good conductor of electricity, but in its purest form, called distilled water, it acts as an insulator. Distilled water is, therefore, used in batteries as an insulator.
We use various electrical appliances every day. Without the help of insulators, the use of electrical appliances is impossible. The parts of the electric appliances that we touch are covered with insulating material. For example, plugs and switches are covered with an insulating material such as plastic, and the wire attached to the plug is a metal wire, which is a conductor. So conductors and insulators work hand in hand.