Part 3: Insulators

Some elements, alone or in combination with others, form substances which resist the flow of electricity. Materials with a high resistance to the flow of electricity are called insulators. Common insulators include air, glass, rubber, oil, ceramic, dry paper, and plastics such as bakelite, Mylar, and polystyrene. A vacuum - the absence of any material - also prevents the flow of electricity.

Insulators can be used in electronics to prevent the unwanted flow of electricity, or to store electrical charges in capacitors. When used to store a charge, insulators are also known as dielectrics.