PC Hardware


The CPU (central processing unit) is the heart and brain of the computer. This one component or "chip" is responsible for all the number crunching and data management. It is truly the centerpiece of any computer. It is so important that whole generations of computer technology are based and measured on each "new and improved" version of the CPU.

When we refer to the CPU, we are usually speaking of the processor. But the CPU also encompasses several other components that support it with the management of data. These components, when working in harmony, make up the computer we know today. The following table lists these components.

Component Description
Motherboard The large circuit board found inside the computer. Without it, a computer is just a metal box. The motherboard contains all the remaining items in this table; for all practical purposes, it is the computer.
Chip set A group of computer chips or integrated circuits (ICs) that, when working together, manage and control the computer system. This set includes the CPU and other chips that control the flow of data throughout the system.
Data bus A group of parallel conductors (circuit traces) found on the motherboard and used by the CPU to send and receive data from all the devices in the computer.
Address bus A group of parallel conductors (circuit traces) found on the motherboard and used by the CPU to "address" memory locations. Determines which information is sent to, or received from, the data bus.
Expansion slots Specialized sockets that allow additional devices called expansion cards or, less commonly, circuit boards to be attached to the motherboard. Used to expand or customize a computer, they are extensions of the computer's bus system.
Clock Establishes the maximum speed at which the processor can execute commands. Not to be confused with the clock that keeps the date and time.
Battery Protects unique information about the setup of the computer against loss when electrical power fails or is turned off. Also maintains the external date and time (not to be confused with the CPU's clock).
Memory Stores temporary information (in the form of data bits) that the CPU and software need to keep running.


The following table lists some common devices, known as peripherals, used exclusively for output.

Device Description
Printer Generates a "hard copy" of information.
Monitor The primary output device. Visually displays text and graphics.
Plotter Similar to a printer, but uses pens to draw an image. Most often used with graphics or drawing programs.
Speakers Reproduce sound. Optional high-quality speakers can be added to provide improved output from games and multimedia software.