Computer Questions: How Pcs Work

Basic computer operation. Explanation of input/output operation as well as definition of which devices are used for either input or output.

The question of how a PC, or personal computer, actually works is one that requires either a good amount of technical background, or an abstract way of thinking. For the purposes outlined here, let's go over the more basic aspects of PC operation, and perhaps focus on one or two key issues.

A personal computer requires one basic component in order to function properly. A user. A user will input information though a device such as a keyboard, a mouse, or, in some instances, voice. Once the data has been introduced through one of these mediums, the brain of the computer, or its processor, will calculate it and return a response to one of the PC's output devices. Output devices on most PCs are monitors, keyboards, speakers, and any other peripheral device connected to your PC.

Sounds basic? It's just a little more complicated, of course, but this is the basic input/output upon which personal computing is based. Now, let's look a little closer.



You sit down at your computer to compose an e-mail to a friend. If your PC is not turned on, you press the on switch. This is commonly known as "˜booting' the machine. By the way, don't forget to turn your monitor on, or you won't be able to see what's happening. This is also known as the "˜output'. What actually occurs at a boot is this;

assuming your computer has not been changed from its factory settings, your computer will search for a "˜boot record'. A boot record is a configuration file which tells the PC which files to start up with. First, your PC will look in your floppy drive. This is because the earliest PCs ran on DOS, or Disk Operating System, an operating system which relied on data disks as input. The development of RAM (random access memory) as well as larger hard disks changed that. More on that later.

If there is no floppy disk in your A: or B: drive, then the PC will continue on to the C: or hard drive. This is usually a machine's main drive. It is where the configuration files are kept which will set up the PC's operating system. The configuration files are read, and your machine's operating system is set up accordingly. A popular operating system, or OS, is Windows. There are also computers made by Apple which use an OS called Mac OS, and there are operating systems which professionals or specialists use such as Linux, UNIX, OS2, Debian, DOS, and NetWare. Once your operating system is loaded, your computer will wait for you, the user, to input data so it can get to work.

Once data is inputted, the first thing your PC must do is convert it to machine, or binary language. This is the language which your computer understands. It is a series of 1s and 0s, 1 being "˜on' and 0 being "˜off'. These represent electrical pulses, which is how your PC "˜reads' the data it is being sent. The processor is the brain of the computer. It is a square shaped box located on your motherboard, inside the main part of your PC. Your processor can read the input, since it is converted to binary language, and instruct the various components accordingly. The information is then "˜read' by your system's RAM, or Random Access Memory. There are different types of RAM, and they have different ways of completing their job function, but the RAM's basic job is to interpret data. The way it does this is by reacting to either a 0 or a 1. For each "˜1', the RAM will react positively, for a "˜0', negatively. Sets of ones and zeroes are sent to the RAM at a rate of thousands of times a second. You may have heard the term, "˜data transfer rate'. This refers to your PCs ability to "˜read' the input, and then "˜write' it to your disk, or hard drive. The RAM is constantly filling and clearing. RAM does not retain memory, however. Once a function has been completed, the RAM will empty out. Likewise, if the computer is shut down, or restarted, the RAM will clear.

The end result is that once read and written, data is sent to the output devices. For example, a typed word, is interpreted into binary language by the processor, and sent to RAM. RAM examines it, and finding it to be text, sends it to the monitor by way of a word-processing program. You see the text displayed on the screen and decide what, if anything, to do with it. If you decide to print it, then the data is sent, again in binary language, to a printer, which will then perform its job function, and output text onto a sheet of paper.

This is an extremely elementary view of a computer system. The science of computing is still a relatively new field, and the basics we have outlined here today hopefully will give you an idea of how the input/output, or I/O system works.

Note: Do not remove the cover, nor attempt to examine any of the components inside your PC unless you are a trained technician. A personal computer is extremely sensitive to static electricity, and mishandling of components may destroy your PC.

© High Speed Ventures 2011