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A Beginner's Guide to Computers: Parts of a Computer & How Computers Work

Parts of a Computer


A computer is made up of four essential parts: the system unit, monitor, keyboard, and mouse. It would be very hard, if not impossible, to operate the computer if one of these were missing. You could, of course, still use the computer without a mouse if you memorized all the keyboard shortcuts, but the graphical nature of most programs nowadays has made the mouse an indispensable part of the computer.

The system unit is the main part of the computer where all the action takes place. It houses all the components that make your computer run. Many people mistakenly refer to it as the CPU when in reality the CPU is just a small chip inside the system unit.

Understanding The Parts Of Your Computer (For Kids)

What's Inside Your Computer?

The term "computer" has also been loosely used to refer to the system unit. The system unit is composed of the following main components:

  • Central Processing Unit
    The central processing unit or CPU is like the brain of the computer. Here is where the machine does its thinking.

The most well-known processors are probably the Intel Celeron family, Intel Pentium family, and now the Intel Core family. To put it simply, the Celeron series is for those who use their computers mainly for word processing, using programs such as Microsoft Word or Excel; the Pentium series is for those who are into multimedia such as music and video; and the Core series is for computer users who do a lot of multitasking.

  • Random Access Memory (RAM)
    Usually referred to as "memory", RAM is second to the CPU in determining your computer's performance. It temporarily stores your computer's activities until they are transferred and stored permanently in your hard disk when you shut down or restart.

Memory cards can be 128MB (rare nowadays), 256MB, 512MB, 1GB, or 2GB. A lot of older computers can hold up to 1GB of RAM only. Newer ones however, can have as much as 2GB and even 4GB (by using two 2GB memory cards). The more memory your computer has, the faster it will respond. But not all motherboards are equipped to hold large memory cards so read the manual first and check the maximum RAM your motherboard can support.

  • Hard Disk Drive (HDD)
    The hard disk drive, more commonly known as the hard drive or hard disk, is where all data and programs are stored in your computer permanently, unless you delete them. Generally speaking, a hard disk with a higher capacity is always better.

The more common hard disk storage capacities are 40GB, 80GB, 120GB, 160GB, 250GB, 400GB, and 500GB. It's always a good idea to choose a hard disk with a large capacity especially if you want to download and store movies - an average high quality DVD movie can take up more than 4GB of hard disk space!

Motherboards usually have a LAN port for networking and internet, an internal modem for internet connectivity, and built-in USB ports for your USB devices such as printers and flash drives. Newer motherboards also have 4-6 SATA ports for your SATA devices such as hard drives and one IDE port for your CD/DVD drive.

Looking Inside A Computer

Take a tour inside the computer and see the main parts of the system unit.

Now that you know the parts that are inside your computer, it's time to learn how these parts interact with each other when you turn on your computer.

How Does Your Computer Work?

This video illustrates and explains in layman's terms what goes on inside your computer.


grace matthew on November 05, 2015:

i love this page so much

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jen on June 20, 2014:

I learn more about you how to handle and care the computer

Damas on February 04, 2014:

I appreciate ur work Susan,it is my first time in this site bt am addicted to it.U have really broaden my mind concerning computer basics,keep it up baby.

varun haridas on May 11, 2013:

the computer new generation

Emmanue Marosi from Madang, Papua New Guinea on April 17, 2013:


AccountPending on February 25, 2013:

Thank you very much, I'm doing a report for school so this helped a lot! I'm definitely going to dirict my friends over here to learn about your hub! Rating 10 out of 5 stars!

jewel on December 11, 2012:

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treevas1 on April 11, 2012:

computer is computing our mind ... :)

fakrudin on March 23, 2012:

good job

chris on March 22, 2012:

thanks a lot

kadex018 on January 15, 2012:

nice hub! i wish that i met you someday.. i love you so much

Susan Ng Yu (author) on August 18, 2011:

Thanks. I'm used to teaching kindergarteners hence the simple language. :)

terence on August 18, 2011:

You have some very well put practical points made here. As you may see from my Hub I am interested in computers and one of the biggest barriers to getting people to use computers is the jargon and the complexity and this really helps.

sheena mae abo on August 11, 2011:

i love you

michelle nillama on August 11, 2011:

thanks verry much ..................... i would like to learn more about the computer............

Susan Ng Yu (author) on July 22, 2011:

Thanks, everyone. :) And wizdom, what do you mean?

wizdom on July 18, 2011:

its important 4 me to know d relevance of csc to human society

seanokeng on June 21, 2011:

thanx 4 help

Emima on June 15, 2011:

itz very useful for me to know the detailed xplanation abt the computer

MDF Recovery on February 22, 2011:

You have done a fantastic job here for the beginner.... Keep Writing....

nakachwe on December 26, 2010:

you people have helped people

Donna Oliver from Midwest, U.S.A. on November 07, 2010:

Thank you for a great hub!

ecinev_11 on September 21, 2010:

thanks ..

lindsays5624 on September 19, 2010:

You have some very well put practical points made here. As you may see from my Hub I am interested in computers and one of the biggest barriers to getting people to use computers is the jargon and the complexity and this really helps.

Julie Rhea Juaner on June 12, 2010:

I'm overwhelmed!

Susan Ng Yu (author) on June 10, 2010:

Thanks for the encouraging words, Martin K. Glad you stumbled upon my article. :)

Martin K on June 09, 2010:

Hey Susan Great Post, I'm a techie myself, I stumbled upon your site and it caught my attention. I really respect your approach to your client's , it's rare to find this kind of service on the net. (I use the same ethics on my site) You mentioned (Negatively) that sometimes you oversimplify, I say "Oversimplifying is underated" Trust me, Keep doing what your doing, there's nothing wrong with simplifying. I love the Vids, Nice, simple, Easy to understand, This is truly and Excellent Post for the newbie learning computer basics. Good Work.

mr weed on March 26, 2010:

this websit helped a lot on my question

juan on March 03, 2010:

so helpful, thanks!

TANMAY on February 17, 2010:


mike on February 08, 2010:

helped a lot thanks :)

gramsmith on December 04, 2009:

You have posted very helpful information for beginners.Now they can easily handle their computer's............

sisters oregon on November 17, 2009:

Great Hub very informational!

abigail on October 21, 2009:

computer of parts

Network management tools on October 21, 2009:

Thanks this is like step by step of learning, Though we all use computer but most of us do not know about its components and how they work.

Your guided tour is surly gonna help people like me.

Susan Ng Yu (author) on October 15, 2009:

Thanks, Rajkumar. It has been fixed. :)

Rajkumar on October 14, 2009:

Nice ya,

Plz check out there is little confusion in RAM

2GB and 4MB u mentioned Its 4GB

Susan Ng Yu (author) on September 25, 2009:

Thanks, Elizabeth. Glad you found it helpful. :)

Elizabeth_Reynera on September 24, 2009:

..,hi susAn!just want to say that hubpage contains valuable informations! ..,ahm'keep up the good work..!

BETH on September 24, 2009:

..,elow! Its been so niCe! goOd job susAn1

Gener Geminiano from Land of Salt, Philippines on September 24, 2009:

I guess laptops and notebooks are more convenient and practical to use rather than desktops that are bulky and have lots of wires and connections LOL... I would rather buy a laptop or notebook as replacement for my laptop than buying desktop computers which depreciates sharply as time goes by...

jade on September 09, 2009:

thankyou for makin the facebook

BOITUMELO RASEEPE on August 31, 2009:


Susan Ng Yu (author) on August 25, 2009:

Hi, md. I'm guessing you would need a computer with high specs to run certain programs? :O I use a few resource-heavy programs such as Adobe Premiere CS3 and my Intel DG31PR motherboard, Intel Core 2 Duo E6550 2.33GHz processor, 3GB RAM with 1TB hard disk does just fine. :)

Thanks, klenn. Keep coming back. :)

md on August 24, 2009:

how can i build a pc very suitable for making architectural design like those used by engineering student????

klenn on August 23, 2009:

wow! its so nice,,, this is my first time in this web sites but i am very appreciates,,,because the explanation is very clear,,,

Susan Ng Yu (author) on August 20, 2009:

Thanks, Jonty. :)

jonty on August 10, 2009:

wow .... this is awesome hub .... very nicely explained ... very informative ..... well written ..... keep up the good work ..... god bless u ......

Susan Ng Yu (author) on May 28, 2009:

Thanks, BadCo. You just made my day. :D

badcompany99 on May 27, 2009:

You said I was good at humour but you young lady have a skill of taking a topic, making it short, interesting and full of all the facts, so you have a talent my friend ; )

sepiroth from Bohol on May 13, 2009:

Nice hubs, Teacher Susan, I have also hubs about cmoputer troubleshooting hope you liked it too....

Susan Ng Yu (author) on May 11, 2009:

Thanks, frogyfish. I'm glad my geeky-ness could be of service. Hehe. :D

frogyfish from Central United States of America on May 10, 2009:

Thanks for this hub, Susan Ng. I have bookmarked it for future use. Like you said you're a wonderful 'geek'. Wish I was....:-) And thanks for your nice words on my hub too!

Susan Ng Yu (author) on March 27, 2009:

Thanks, jhiivan and Computer_Nerd. :-)

Computer_Nerd on March 25, 2009:

This is a very good hub! Perfect for anyone who wants to know more about computers without reading a novel about the PC.

jhiivan ngaosi on March 20, 2009:

ur so awsome and ur hub is nice too,,,,good job

Susan Ng Yu (author) on November 17, 2008:

Hi, liliam. Have you tried doing a search on Google Images? :-)

liliam on November 14, 2008:

susan I need information pictures of the parts of the computers but it has to be very modern with the web cam

karl on July 03, 2008:

thanks for helping

Susan Ng Yu (author) on April 29, 2008:

Haha! Welcome to my kindergarten class, William. :D

William F Torpey from South Valley Stream, N.Y. on April 28, 2008:

On behalf of all computer dummies, I just want to assure you, Susan, that there's no such thing as "too simple." Please keep writing for us kindergarteners.

pjdscott from Durham, UK on April 24, 2008:

This is a very precise and useful hub. Sometimes people get scared by the technology and jargon, but you have explained it beautifully. Great stuff.

Susan Ng Yu (author) on April 22, 2008:

I'm so happy you think so, Pete. :) I was worried it would be too simple for grown ups. I'm actually in the process of making our school's computer handbook and it's going to be used by kindergarteners, so I tend to oversimplify things a bit. :P

Thank you, thank you. :)

WeddingConsultant from DC Metro Area on April 22, 2008:

Susan you are awesome. And your hub is great too! This is a great beginner's guide to a computer.

Susan Ng Yu (author) on April 22, 2008:

Thanks, Earl. :)

Susan Ng Yu (author) on April 22, 2008:

You're welcome, William. Glad I could help. :)

Earl S. Wynn from California on April 21, 2008:

Very very nice. A beautiful comprehensive overview of modern computer technology, put together so seamlessly and with such skill that I can only marvel at it's artifice. Excellent work!

William F Torpey from South Valley Stream, N.Y. on April 21, 2008:

Thanks, Susan. I've used computers for a long time, but only for word processing. Since I joined HubPages I've been trying to learn the basics, but it's going very slowly. This basic information helps.

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