How a personal computer works   

Personal computers (PCs) are versatile machines that help people accomplish tasks faster with a greater degree of accuracy. They consist of hardware, software and an operating system. They are usually used in business and at home for a wide range of tasks. PCs come in desktops or as mobile computers such as laptops and notebooks. You could say that today's smartphone is a small personal computer. But for this article we'll sticke to the traditional definition of a PC.

The Hardware Component

The most essential part of a PC’s hardware is the Central Processing Unit or CPU. The CPU is often referred to as the "brain" or the command center of a computer because this is where the processes are co-ordinated. The CPU is mounted into a motherboard which provides the ports, sockets and slots to connect all the other hardware devices to the CPU. The motherboard enables these various hardware devices to communicate with each other and serves as a bridge to carry out the commands coming from the CPU. In this way, the functions of the different hardware devices are brought together to work as one complete unit. The most common hardware devices in a PC include hard drives, memory modules, modem, network cards, sound cards and video cards. Though nowadays, the network, sound and video card features are built-in into the motherboard. Other hardware devices connected outside the computer such as the monitor, keyboard, mouse and printer are classified as peripherals.

The CPU starts to communicate with the motherboard once the PC is turned on. It will then launch the Basic Input Output System or BIOS which is saved in a ROM chip placed on the motherboard. The BIOS then will identify and initialize the hardware devices needed for the computer to function properly. Such hardware devices are the memory modules, hard drives, keyboard, mouse, video card, monitor, floppy and CD/DVD drives. The next thing the BIOS does is to look for an Operating System which will be located on the hard drive, CD/DVD or in a network drive. Once located, it loads the Operating System into the memory giving it the authority and control over the PC. This is otherwise known as the booting process.

The Operating System (OS)

The operating system manages almost everything that the computer will do. From issuing commands to the different hardware devices to do their job to coordinating all the software and providing a graphical, user friendly interface for the wetware (human) operator.

The OS acts as a liaison amid all the software and hardware components. It distributes the resources of the computer to the hardware and software in a systematic way. These resources comprise of temporary or permanent storage areas and input and output devices. PC's and laptops don't run without operating systems. And they don't run very well with them sometimes (if you're running Windows!).

Software

Of course, the Operating System is software. Software is an intricate set of commands and instructions with an exact order of execution. And it's software that brings your PC to life and enables it to do the truly useful things it was designed for. Email, browsing, storage and playback.

All in all the PC is probaly the most complicated and useful machine every created by the human race. Remember that every time you switch it on and count yourself lucky you were born at a time when you can buy one of these devices for the same price dinner at an expensive restaurant!

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