There are three ways an object can be charged. One is friction. If two objects are rubbed together, then some of the electrons will have a stronger attraction to one of the two objects, and some of the electrons will transfer over.Objects can also be charged through conduction. Charging by conduction occurs when objects touch and an electric charge is transferred. If you walk across a carpet and get a shock from touching a metal doorknob, this is from conduction.

Objects can also charge without any contact. When dust builds up on a computer screen, and the screen is turned on, the dust gathers a charge. When a neutral dust particle comes near the screen, the screen induces an opposite charge on the near side of the dust particle, attracting it to the screen.

Electricity is basically electrons moving quickly from atom to atom. An insulator is a substance in which the electrical charge cannot move to another object. Substances such as plastic, rubber, and glass are insulators. A conductor is on object through which an electrical charge passes easily. Most metals are good conductors. A semiconductor allows the electricity to travel through them, but not as easily.