Insulation is made of materials that are poor conductors, such as glass, plastic, or rubber. They are used in an attempt to keep an electrical current within safe boundaries. For example, the plastic coating on an electrical wire is insulation and is designed to keep the electricity in the wire. Insulation is used for building homes, businesses, protecting wires in a building and many other uses. By putting insulation over items it helps keep people safe from hazardous items.