This central processing unit, or chip, is usually called the CPU . Schools operate bus systems to transport students to school. If the seats are wide, more students can sit side by side in each row, and more can travel at once. Similarly, computers have bus systems that transport information from one part of the computer to another. The permanent storage disk that stays in the computer is called the hard drive .
Peripherals are parts added on to the computer to allow it to do special tasks.
A printer is a peripheral. Usually home computers make this connection by using a peripheral called a modem . Computer instructions are written in a code that contains only zeros and ones. This is called binary code . Electricity entering the computer first goes into the power supply .