Parts of a Computer

Most people are frightened by the idea of opening up a computer. They see hundreds of small electronic components in a confusing array, with dozens of mysterious wires leading everywhere. They are afraid to touch anything for fear of destroying a thousand-dollar machine.

Yes, it's true that you could damage a computer is you don't understand it. However, computers are really not too hard to understand. When you open the box, there are really only about ten or so different parts. Once you know what they are, it becomes much simpler to work with.

The main parts of a computer are these:

  • Motherboard: the main platform which everything is connected to.
  • Expansion card: added to the motherboard, these smaller boards add features
  • CPU: the "brain" of the computer
  • RAM: also called "memory"; the more you have, the more software you can use
  • Hard Disk Drive: also called HDD (or recently, SSD), this stores your main data
  • Optical Drive: CD, DVD, or Blu-ray
  • Power Supply: This takes the power from the wall plug, and changes it so the computer parts can use it
  • Case: the container for the computer; includes a power button and extra USB ports

There are other things you might find, but these are the main parts. All of them can be connected or disconnected simply by pulling or pushing, clamping or unclamping, or by using a screwdriver. You don't need to solder or use special tools unless you are doing something unusual.

One of the most common operations a user might do inside a computer is changing RAM memory. When a computer is sold, it usually has less RAM than the maximum in order to lower the price. Many people need more RAM, however. Shops will usually sell the RAM and then install it for you for free, but some people don't find out about the RAM needs until later.

Fortunately, RAM is usually easy to install. After turning off the computer and unplugging the cables, you can usually open the case with a button-push or by removing a few screws. The RAM slots are quite visible. Just make sure the RAM is facing the right way (you cannot push it in if it is backwards), then push the RAM down until the locks click. And that's generally all there is--close the case, and you should be ready to go.

Not everything inside is that easy, however. The hard drive can be changed, but requires a few cables to be connected in the right wat, and needs to be screwed into what is called a "drive bay." The CPU can often be changed; although the CPU itself is fairly easy to pop in and pop out, the cooling fan can be difficult to take off and put back on. And so on.

In the following sections, you will learn more about what each part does and how it is used. If you know these points, it is not too hard to make your own computer!


That big green square thing with everything on it. Computer pizza!
Max out the RAM if you can--you'll be able to use more and more powerful software.
The more you have, the more files you can save.
Music, Movies, Data...
What are all those wires for? What are those holes on the back of my computer?
Cases can make the computer look cool; power supplies let them run eveything.
Perhaps you'd like to join the Computer Making Club?