The Parts of a Computer Explained for the Average Person

By Charles Buege, Virtual Lab and Spark Event Coordinator for Fuel, charles.buege@fuelusergroup.org

This article was originally published in March, 2021, and with the relaunch of the Fuel Blogs, I wanted to get this article re-published with some minor updates.  Thank you very much to the hundreds of people who read the original article on the old Fuel site and I look forward to hearing back from any new readers this time around!!- Charles Buege, June, 2024

First off, this is a non-technical article. This is a very different direction from my normal articles, but as you read, you’ll see that this is the intention. I’ve been working with computers for over 30 years. Even back in junior high school, computers always came easily to me. I’m lucky like that. I simply always just “knew” how to make a computer do whatever I wanted it to. I just seemed to inherently know how to “bend it to my will” as some of my friends would say. Needless to say, others I know aren’t as fortunate, so I have been asked many, many times over the years about the different parts of the computer, what they do, etc.

I want to dedicate this article to my dear friend, Stephanie, who asked me point blank one day: “Why don’t you just write an article about this since you’re writing all those other computer-techy articles?” I have to say, she really brought me up short with that simple question. Actually, she had a really good point ― why would I not write an article on something this basic that many people could potentially benefit from? So here it is ― my article to define the different parts of a computer into terminology that the average person can understand.

Case/Chassis

I want to start off by making one thing very clear. You know the box that is under your desk or sitting next to your monitor that you turn on to start your computer? That is most definitely not and should never be called your “hard drive”. That is your computer. More properly, you are actually looking at your computer’s case or chassis. The hard drive is a component that we will address later on in this article. It is not the entire box that is sitting there. Okay, thank you. Now that I have that out of my system, onto the rest of this section.

The case or the chassis — call it what you will — is the frame that houses all of the components of the computer. It can be a simple black box, have all kinds of bright lights on it or if you’ve seen some of the really creative designs out there today, it can be a glass case mounted on wood paneling. Why, you might ask, would someone mount a fully functioning computer case to their wall? Why not? Many people who have done this have been building computers for so many years that they needed a new challenge and simply wanted something different ― so they decided to just go for something new. 

Motherboard

The motherboard is the piece of electronics that you use to connect everything else together. It is the roadway that allows all of the other parts ― central processing unit (CPU), random-access memory (RAM), video card, hard drive, cache, power supply, etc. — to communicate with each other. What is so special about a motherboard? Well, the motherboard is the core of connecting everything together so before you start to get your parts, you need to have some kind of idea as to what kind of computer you’re going to start to build. Basically, you want to know how “big” of a machine you’re going to want to build, how big of a frame you’re going to need and how many components you’re going to want to hang off of it. Once you have that information identified, you’ll have a better idea of what motherboard you’ll want. I tend to equate the motherboard as the “roadway” within the computer as it gives you the paths for all of the equipment to communicate with each other. I also avoid using the term “highway” so that people don’t get this term confused with “information highway” or references to the internet. People who have next to no hardware experience tend to mix very similar phonetic terms easily, hence the distinction.

CPU

The CPU, or central processing unit, is definitely the brains of the computer. But you’ve heard that before. But you’ve also heard terms like “gigahertz” and “cores” with regards to the CPU also. It’s pretty simple actually. Where the CPU is the brain of the computer, the gigahertz (GHz) of the computer is how fast the computer can think. The higher the number, the faster it can think. As far as the number of cores, that’s also pretty easy. The number of cores in a CPU allows the brain to think of more than one thing at one time. The more cores in the computer, the more things it can think about at one time. This means that a CPU that is 2.0 GHz with four cores won’t be as fast as a CPU that is 3.2 GHz with sixteen cores. Does this mean that the 2.0 GHz with four cores will not be able to take care of your needs? Not necessarily ― it might, but it will just do it at a slower rate. So, in summary, the CPU is the brains, with the gigahertz being the speed of the brain and the cores being the number of things that the brain can think about at one time.

Heat Sink/Liquid Cooling System

CPUs generate a lot of heat running all of their calculations. If you don’t disperse that heat, the CPU will become damaged and stop working. So, you need to get something that will disperse that heat and that is what a heat sink or liquid cooling system is for. The heat sink looks like layers of metal ― like a loaf of bread ― with space between each layer. It pulls the heat away from the CPU, disperses it into the air that flows between the metal layers and keeps the CPU at a temperature that allows it to run optimally. A liquid cooling system does the same thing, but in a slightly different manner. The component that attaches to the CPU performs the same task as a heat sink, but transfers the heat to the liquid within the pipes. That liquid is then circulated to the fans, cooled, and returned back to repeat the process.

RAM (Random-Access Memory)

When people talk about RAM, or memory ― both of these terms are interchangeable ― people like to talk about it with regards to “how much you can think about at one time.”  Personally, I disagree with that. I see RAM as being how big of a table you have in front of you to lay all of your work out on. The more RAM you have, the bigger the table you have to spread out all of your work.

RAM is always increasing in size, from kilobytes to megabytes up to gigabytes of today’s desktop computers. Eventually it will move beyond that, but for today’s computers, we are looking at gigabytes for the range in which we measure memory. At the time of the writing of this article, 16 to 32 gigabytes of RAM are considered pretty good. With that much RAM, you’d have a pretty good sized table to spread stuff out on.

Now, when you keep your computer on for days and days at a time, your table becomes more and more cluttered ― you never have a chance to fully clear it and more and more “stuff” just keeps piling up on it. When you restart your computer, it’s like taking your arm and quickly swiping it across the table to clear some of the stuff off of and into a box that you can then put to the side. But, when you fully shut down your computer, it’s like the actual cleaning and organizing of the table ― removing everything from the table and putting it into its proper place.

On this note, I do want to mention one thing about shutting down a computer. With Windows 10 and 11, and it could be true in earlier versions of Windows but I’m not positive, be sure that you turn off the following feature: Control Panel -> All Control Panel Items -> Power Options -> Choose what the power buttons do -> Click “Change settings that are currently unavailable’ if necessary” -> Uncheck “Turn on fast startup (recommended).”  With this option, even if you “shut down” your PC, the machine still goes into a hibernate/sleep mode  This hibernate/sleep mode, to continue the ‘table’ analogy, simply takes a snapshot of what is on your table so that when you turn the computer back on, everything that was there is put back in the same place.  It doesn’t allow for any kind of clean-up to occur.. I don’t like this and don’t recommend it. Yes, it does mean that your machine does take longer to power up and shut down, I concede this point, but it also gives your machine a more complete shut down and allows for a cleaner machine upon startup.

Video Card

A video card is what you use to connect to your monitor, TV or whatever device you have for a display. Video cards have their own processors on them, called graphical processing units or GPUs, as well as their own RAM which means the main computer doesn’t need to share its resources as much. It also means that since it has its own resources, it can show its pictures faster and crisper. Why would you want a bigger,  better or more expensive video card? Well, this is going to be for one of two things primarily: either high end gaming or high end graphics and/or video work. Either one of these is going to run faster and better if you have a better video card  because it will allow the game or graphics/video editing program to process its work faster and more efficiently ― because that graphical work is optimized to run on the video card’s processor instead of on the main processor.

Think about it like this: If you need an oil change, you can take it to your car dealership. Sure, they can do it, but it isn’t something that they specialize in and do exclusively. The wait will be longer, you’ll have to schedule your appointment further in advance, etc.  On the other hand, if you take it to an oil change location where that is all they do, you’ll be in and out in a couple of minutes. That’s like using a video card ― that “oil change location” will handle the processing much faster and more efficiently than a standard processor like your “car dealership” would. Yes, the dealership would get the work done but it would still not be as efficient or as fast.

HDD/SSD/Storage

HDD stands for hard disk drive. SSD stands for solid state drive. Both of these mean “storage.” This is where you have your files saved. When you see a C: drive, D: drive, etc., those are your HDD and/or SSD drives. What is the difference between HDD and SSD? It has to do with how they work on the inside. HDD refers to older drives that work with what is referred to as “spinning disks.” These spinning disks, or platters, will rotate around really fast and an arm moves back across each of the surfaces in a manner very similar to a record/LP and will save the data to the platters using magnets. SSD, on the other hand, uses electronic transistors to store the data in 1s and 0s. The important difference between the two is this: SSDs do not have the rotating platters that HDDs have. This means, with less moving parts, they are more robust and don’t fail as easily. But, being newer technology, they are more expensive and smaller in size. So, as of now, HDDs have higher data capacity, are lower in price, slower and more likely to have mechanical failure. SSDs are lower in data capacity, higher in price, faster and less likely to have mechanical failure.

Power Supply

As you probably realized by this point, all of the parts of a computer need electricity to run. The power supply is what you will plug the power from the outlet into to get power to the computer. The power supply is what will then distribute power to the different parts of the computer — motherboard, drives, fans, video card (if necessary), etc. Now, as you’ve had to put some planning into place before for other parts of your computer, this is another time where you’ll need to do this. Power supplies come in different power levels called watts. On average, you’d be dealing with a power supply of about 800 to 1000 watts for your average desktop computer.  If you have a higher-end video card, you will want to increase to a higher wattage - around 1500 watts for example.

Once you have an idea of what components you want to put into your computer though, you’ll want to look at the amount of wattage each component could potentially consume to make sure that the power supply that you’ve decided on is enough for you. You definitely want to make sure you don’t get a power supply that is too low because if you don’t have enough power, your machine won’t even be able to turn on or you may ruin some of your components like your video card.. On the other hand, if you have a power supply with too much power, you’ll be fine. You won’t “burn out” your computer if that is your concern, rather you’d just have “wasted capacity” on your power supply. If, eventually, you’ll use the power, you’re better off buying a more powerful power supply early on in my opinion.  If you’re not sure or if cost is an issue for you, then, you can get a power supply that is “middle of the road” and you can always upgrade it later on if you find you need to. 

Here’s how you can think about it. If you get, for example, a 500-watt power supply, but then purchase a top of the line motherboard, processor, RAM, video card, etc., when you try to turn the computer on, there just won’t be enough power. It’s like trying to have a six-year-old push a full size truck ― it just won’t work. On the other hand, if you get a 1400-watt power supply, purchase an average motherboard, processor, RAM, video card, etc., when you turn the computer on, it’ll be more like having a large football player being asked to push a really small smart car ― they won’t have much trouble doing it at all. 

Conclusion

This list of components is intentionally vendor-agnostic. This way, this guide is appropriate to anyone curious to know more about computer parts.  I hope this article assists with providing a very basic, simple introduction, so that even someone with zero hardware knowledge will now have a starting place after reading. 

Charles Buege is the president of Buege Enterprises, an IT consulting company out of Wheaton, IL.  Working for Fuel in many capacities over the last several years, he’s also thrilled to be a formal part of the team now.  He also runs an IT-based Meetup group called “The IT Crowd.”