All the data stored in your computer - every word, picture, number, and sound - is captured as a series of electrical pulses that are either on or off. A number system called binary is used to represent these pulse with "1" meaning ''on'' and ''0'' meaning ''off''. A single binary digit, known as a "bit", switches a single switch on or off. By linking together these switches, the computer can carry out the complex operations we demand.
