What is... Inside your computer

What you should know and understand about your computer

Author:  Tina Landers

Quite simply, a computer is a device which processes instructions. It cannot "think" the way we do, though you could be forgiven for believing it had a personality, and usually a nasty one, every time it plays up.

It's a wonderfully intricate device, demonstrating the genius of the many individuals and groups who contributed to the final product that sits in front of you right now. For us non-technical genius types, here's a simple way of understanding how your computer works.

For the purposes of this exercise, we're going to ignore the masses of wires, circuits, switches, etc that sit inside your computer. Instead, we're going to look at the components that you, the computer user, can control and therefore should know about and understand.

Your computer functions in a similar way to an office. In fact, the workings of an office provide an excellent anology to the workings of a computer. So, to get started, picture your favourite room at home and imagine it’s dedicated to being your personal office. It’s a typical office - desk, drawers, filing cabinet, light switch etc. Oh, one more thing, picture your office being run by a super efficient, dedicated personal assistant named XP. XP is so indispensable that your office simply cannot function without him.

Now let's look at the individual components in your computer (the ones you need to know about) and see how they work and what they do:

RAM:  (short for Random Access Memory, commonly referred to as memory) provides a function similar to that of the desktop in our office. It provides the workspace for whatever it is that you are working on. Just as you spread out your paperwork and files on your desktop as you work through them, similarly your computer "spreads out" all the information it needs in it's RAM. Your computer's RAM holds a lot more than just your work, it also holds all of the information that your computer needs to function - system-related files and processes that keep working in the background.

RAM is important because, like your desktop space, if there isn't enough of it or if there's too much in it, working in it becomes restricted. You simply run out of working space and your computer greatly slows down. You either have to free-up some space or get some more.

RAM comes in the form of "modules" (sometimes referred to as chips, sticks or cards) and each module "plugs" into a board in your computer. RAM is a temporary storage medium. As soon as you save and/or close whatever you are working on, it is removed from your computer's RAM. RAM is "volatile", meaning that it does not retain its contents when its power source is disconnected. You've probably heard the words "save your work" - that's because you lose everything in your computer's RAM if the power to your computer is somehow lost. Each time you click "save", your updated work is saved back to your computer's Hard Disk Drive, which is a more permanent storage medium. RAM modules are (relatively) easily replaced or upgraded to accommodate the users needs.

Computer Memory (RAM) being "plugged in"

RAM capacity is measured in MegaBytes (MB) and even GigaBytes (GB). As a general rule, as far as RAM is concerned, more is better than less. You can read a more detailed article about MegaBytes and GigaBytes here.

You do have some level of control over your computer's RAM usage, and you should exercise that control on a regular basis to ensure the efficiency of your computer.

You can read a more detailed article about RAM and how best to manage it here (Recommended Reading).

Also, take a look at our TOP TIPS at the end of this article.

HDD:   (short for Hard Disk Drive, often referred to as hard drive, storage, disk, hard disk or any combination thereof) is a permanent storage medium. It comes in the form of a sealed metal enclosure containing one or more spinning disks (which look like CDs), each with a corresponding "head" which "reads" and "writes" information from/to the disk. Information is magnetically encoded to the metal disk, ensuring it stays there when the power is switched off.

Inside a Hard Disk Drive's enclosure

A Hard Disk Drive functions similarly to the filing cabinet in our office. It holds all of the data (information) files and all of the program (instruction) files that you and your computer use. When you click an icon on your desktop, the associated program files (think of a computer software program as a set of related instructions with a common purpose) are opened and placed in RAM, along with any data files (data files could be any combination of information/picture/music/email etc) that you will require for your work. Access to and from your Hard Disk Drive is controlled through the Operating System (our dedicated personal assistant Robot XP).

Hard Disk Drives are (relatively) easily replaced or upgraded to accommodate the users needs.

Hard Disk capacity is measured in GigaBytes, ie. more GigaBytes = greater storage capacity. Hard Disk speed is measured in "access times" of milliseconds, ie. fewer milliseconds = faster disk.

To function efficiently, your Hard Disk Drive requires regular "cleaning" and "maintenance". For your own peace of mind and safety, you MUST "back-up" the contents of your HDD regularly (I know - you've heard that before... so why haven't you been doing it?).

You can read a more detailed article about Hard Disk Drives and how to manage them here (Recommended Reading).

Also, take a look at our TOP TIPS at the end of this article.

Operating System: (also referred to as Operating Software) which, for this exercise we've called Robot XP. The Operating System in your computer controls and manages everything that your computer does. It functions like a super-efficient assistant in our office, fetching information from one place and depositing it to another. It ensures that each of the many components in our computer receives, at the exact time, all of the information that the component needs to do its job.

Operating Systems come in many varieties (Windows XP, Windows 2000, MacOS, Unix, Linux, etc) and are the common thread which link all of the components in our computer. Absolutely nothing happens within any component in your computer without an instruction from the Operating System. When our Operating System gets confused (via conflicting instructions, software bugs etc) everything stops, resulting in a "freeze" of your computer. Generally this results in you having to switch everything off and starting all over again.

Operating Systems are regularly "updated" by their respective manufacturers (Microsoft, Apple etc) to fix issues, enhance security, etc. It is important that you apply these updates to your Operating System as and when they are released.

CPU: (Central Processing Unit, also referred to as processor) is often called the "brain" of the computer. It's function is to "read" instructions, "execute" the instructions and "write" back a result. Think of a calculator in our office, you key in a sequence of numbers followed by an add/subtract/multiply/divide key and up pops a result. The CPU in your computer functions in a similar way, churning through instructions and producing results - millions of times each second.

A CPU generally comes in the form of a "chip" (usually ceramic), which plugs into a board in your computer. Most PC chips take the form of a Microprocessor - a tiny marvel of integrated circuitry. Most all-purpose home computers have one CPU, however there are computers that contain two or more CPUs.

One of the many forms of CPU - This a rather large one

CPU speed is measured in MegaHertz and GigaHertz, ie. greater number = faster processor (often referred to as more powerful because it can process more instructions per second. 

Registry: Your Operating System sets-up and maintains a set of files collectively known as a Registry which it uses each and every time you use your computer. The Registry contains indexed information about absolutely everything in your computer. For example, each time you install a new piece of software, the software "registers" details about itself and its requirements within the Registry. From there on, each time you use that software, your Operating System checks the Registry to determine and ensure the right resources inside your computer are ready and available for that software to use. Picture the Registry as a super-charged card-index file in our office, containing information about each of our associates/contacts. The Registry holds all that and a whole lot more.

The files that make up the Registry

The Registry is often a source of problems that may keep recurring. You may have heard of a "corrupt" Registry - that simply means that the Registry has some inaccurate, incomplete, incorrect or "unreadable" information in it which is causing conflicts and/or issues and/or problems when that information is accessed. It is important that you regularly "clean" and "maintain" your computer's Registry using software designed specifically for that job. You can read more about that here  (Recommended Reading).

Also, take a look at our TOP TIPS at the end of this article.

There are, of course, many more components inside your computer performing a variety of tasks each and every second and there is plenty of information about each of them within this site and even more freely available over the Internet, if they interest you. For the purposes of simply understanding your computer, the above should provide you with a strong basis upon which you can grow or satisfy your interest.

TOP TIPS:

Want to know what exactly is in/on your computer? Here's a great software utility that will provide a detailed overview of all of the hardware and software in your system... and it's completely FREE. Just download, install and run it. It's called the Belarc Advisor and you can get it here. If you'd like to know how to download and install software, you can read a more detailed article here.

Want a free software utility to "clean" your computer? Ccleaner is a simple cleaner that does what it promises and it is available completely free. It's a great start if you currently have nothing doing this task for you. You can read about it and get it here. If you'd like to know how to download and install software, you can read a more detailed article here. Please read the instructions thoroughly before using this product.

What do we use to "clean" our computer? We use a product called System Cleaner 5. It's an "all in one" cleaner and Registry "problem fixer", it's very reasonably priced and keeps our computers performing efficiently. We love this software and highly recommend it. You can find out more and download a trial version here.

How do you keep your Hard Disk Drive "clean" and efficient? There are some great software utilities out there that make it all too easy, and we will be examining the better ones soon. In the meantime, look in your Programs (click on Start then on All Programs), under Accessories (we're talking Windows XP here) you will find System Tools. Under System Tools you will find a "Disk Cleanup" utility (or program) and a "Disk Defragmenter" utility (or program). They're not as good as some of the commercial ones, but they're a good start... and they're free. Go ahead, start your computer spring-clean today, you'll notice the difference. Make sure you "clean" before you "defragment".

Where to find your Hard Disk Drive "cleaning tools"

You can read a more detailed article about maintaining and servicing your computer here.