Some materials allow electric current to flow more freely than others. These materials are called conductors. Other materials are resistant to the flow of electric current. These materials are called insulators. Regulating the flow of electricity is very important in the field of electronics which is why both conductors and insulators are very important when studying electric behaviour.
Conductors
Electrical conductors allow electric current to flow easily because of the way in which electrons are organised in their atoms. Electrons in conductors are loosely bound and can, therefore, move freely whenever a driving electric force is applied. Interestingly, because this same arrangement of atoms, good conductors of electricity, are also good conductors of heat. Heat however, increases a material’s resistance, meaning that its harder for the electrons to move. In general, the best electrical conductors tend to be metals. To this day the most commonly used electrical conductor is copper, which is found in almost all electric circuits and electric components around the world. A superconductor is a material that is a perfect conductor. It has an electrical resistance of zero, meaning that electrons can move with little to no effort. Superconductors are very rare, because they are made of rare metallic alloys and require extremely low temperatures to conduct electrons easily.
Insulators
The opposite of a conductor is an insulator. An insulator opposes the flow of electricity. Insulators are important to keep us, or sensitive electric components, safe from electricity. The wire that carries electricity to your computer or television is covered with a rubber-like insulator that protects you from getting electrocuted. Good insulators include glass, air, and paper.
Semiconductors
Some materials behave like conductors in some situations and like insulators in other situations. These materials are called semiconductors. Semiconductors are very important because they limit the way in which electricity can flow (usually determining the direction of electric current). They are used in more complex circuitry like computing processors found in calculators, smartphones and computers.