Updated: Sep 27, 2020
Previously, I talked about why you would want to build a computer; today we learn what a computer is. Seems like a simple question, but as straightforward as it seems, let's begin with what a computer is not. A computer is not just a monitor. There are all-in-one computers that look as if they are just a monitor, but there are many components inside that unit. Also, there is a lot that separates a monitor from a T.V. Don't make the mistake of thinking a TV is a monitor. There is a reason a small monitor can be just as expensive as a 70in TV, and it's not just because they are marketing to a niche group of individuals. There is a benefit to a specific monitor with unique capabilities. Secondly, a computer is not a tower or computer case - that is just a shell for all of the components of a computer to go into. There are a lot of cases, a lot of designs, and some thoughts need to go into what computer case your will need, but if push comes to shove, you could just lay all your computer parts out on a non-conductive surface, plug them all in, and they would still work. You'll need a switch or jumper to turn on and off your computer, but it would still work by simply being plugged in. So, you could check out what size tower case you need at that point. (I'll show you what I mean later!)
A computer is not a CPU. This a crucial part of a computer, but not a computer. That analogy floating around comparing a CPU to the brain is mostly accurate in describing this. The CPU is only one part of the computer, but many parts make the whole. If you have a CPU in your hand, you are still far away from having a computer. There are many types of CPU's available from different manufacturers. The differences between CPUs can be pretty severe, and the sockets that CPU's sit in are not universal. Thus, a 4th gen. Intel processor will not fit into a motherboard with a 9th gen. processor socket. It is important to plan what you are buying because this will start to dictate your purchases on your computer build.
I am going to continue using the body analogy, if the CPU is the brain, the motherboard would be the spinal area. This component of the computer is where all of the major components are going to attach so that they can send information back and forth from the CPU. There are many different chipsets for motherboards and I will do a deeper dive into them later, but for now, I would just like you to know what components make a computer. The motherboard will mostly dictate the size and capabilities of your computer, so when choosing a motherboard do some extra research and make sure you get what you need.
Next, I would like to introduce you to Random Access Memory, or RAM for short. This is not like a body part, more like the short term memory of the brain. Before the brain (the CPU) gets to process the information, that information needs to get stored and ordered. Yes, a CPU is processing millions if not billions of tasks per second, but it had a lot to do and all those tasks get stored in RAM. There is way too much information about RAM to have a simple one-paragraph informational, so again, this will be explained further in the future.
Speaking of memory, we need storage to make a computer. There are many mediums for storage, HDD, SSD, NVMe M.2, hybrid drives... and I am sure more will be developed. But, for simplicity, this is where data is going to be stored, so this would be the long term memory for the computer. Data like: your operating system, your favorite computer games, office applications, and various other information that will be stored. The bigger the storage space, the more you can hold, but some things make accessing the information faster or slower. HDD, or Hard Disk Drive, uses a lot of mechanical parts, so there are a lot of moving parts. This drive works kinda like a jukebox, a bunch of disks spinning, and a mechanical arm riding atop those disks reading the information. The Solid State Drive (SSD) has no moving parts, as its name implies. It is tiny memory modules inside with a complex circuit board. The advantages of SSD's over HDD's are significant because they are faster, more reliable, and run quieter. The disadvantage is that, currently, they cost substantially more than their mechanical counterparts.
The last memory medium I mentioned above is NVMe M.2. From a marketing standpoint, MVMe M.2 is the major player. There is also SSD M.2, but it is not as widely marketed as the MVMe M.2., which provides some of the fastest transfer speeds available on the market today. However, just like the advantage HHD has over SSD, NVMe M.2 is cost-prohibitive.
The next part of a computer we need to discuss is the PSU or power supply unit. This does exactly what it sounds like, it supplies power to the components of the computer. Computers are really fickle when it comes to power - and the power coming out of the wall is overkill in some aspects. The voltages passing across the computer components are sometimes not even one volt. The power supply ensures that proper power and voltages are being directed to the proper components on the computer. Now, the motherboard still does a lot of voltage regulation, but a good PSU will alleviate some of the voltage regulation the Motherboard will have to do, extending the life of your computer system. Again, just like everything in a computer, there is a lot to discuss about PSU's, like the rating system they have posted on the (80 Plus Gold, Silver, Bronze, etc...) ripple, wattage, but that again will require a deep dive later down the line. A general rule I would like to share about power supplies is to buy one from a reputable PSU maker with a good warranty. The efficiency ratings... well one can argue are mostly pointless, you are not really going to notice a difference on your power bill under normal use, but buy a poorly made power supply and you may have high ripple, higher temperatures, and shorter component life spans. It's just not worth it to purchase a cheaply made PSU.
Optionally, we need a graphics card in a computer so that the information processed can be displayed on a monitor. Now, most CPUs have built-in graphics, meaning that the display port on the motherboard will display your information, but on the off chance you purchased a CPU without built-in graphics support, you're going to need a graphics card. There are a ton of cards out there, but the cheapest video card will display simple graphics, like videos, web pages, and office applications. You'll need a beefier graphics card to play modern computer games, but the quality of the graphics card does not make a computer, it just dictates the quality of one aspect of a computer. Basically, a computer must have a way to transmit information to a display for the user.
Lastly, and circling back to the beginning of this entry, we need human interface devices (monitor, mouse, keyboard, speakers, etc...). These are the devices that you will physically interact with.
So, that about wraps it up. a computer is a human interface devices, a CPU, a motherboard, RAM, Storage, PSU, and a graphics card (sometimes). There are a ton of other components that you can add to a computer to enhance its capabilities or looks, like sound-cards and RGB's, but they are optional.
Keep on following me. I'll be doing deeper dives into each of the topics in this entry