The CPU, Hard Drive and Memory

The CPU, Hard Drive and Memory

The basics of what goes into every computer

It’s understandable to be confused about the Central Processing Unit (CPU), memory, hard drive,

So here’s an explanation in terms that I hope will hep you understand what function these components perform.

The hard drive looks like a stack of three old vinyl records with a needle for each record. New ones don’t have moving parts, just microchips

I’ll start with the Hard Drive, also known as the Hard Disk; this is like your bookshelf, it stores all your application programs; your word processor, spreadsheet, photo editing or picture management software. The hard drive is also the place where the files, images, music, video are stored.  The hard drive also as a special place where your Operating System, Windows or Linux or Mac OS resides. The hard drive is commonly labelled the C drive Some hard drives are partitioned into two or more partitions; giving you a D, E, F etc drives. It’s like partitioning a room, you get more rooms but not more space.

Drives come in different capacities and spin speed, the faster the spin the better.

New Solid State Drives,l SSDs have no moving mechanical components. SSDs are therefore more robust and resistant to physical shock. They are also faster . The price of SSDs has dropped significantly and you should consider an SSD if you are looking to replace your old hard drive.



Memory comes in different shapes and sizes depending on what kind of computer or laptop you have. Image © Raimond Spekking

The memory of the computer is known as RAM, short for Random Access Memory. Memory is like your tabletop; the bigger it is, the more stuff from your bookshelf you can put on it.
If you have small amount of memory – and these days 2GB and even 4Gb can be a small amount of space. Older computers can’t handle more than 4Gb of memory.
There is a workaround whereby the Operating System will shuffle files between the tabletop (memory) and the bookshelf (hard drive) if the tabletop becomes crowded.
This shuffling slows your system down further and increases the wear on your bookshelf (hard drive)- especially if your bookshelf (hard drive) is pretty full.


Eric Gaba, Wikimedia Commons user Sting [GFDL ( or CC BY-SA 4.0 (], from Wikimedia Commons
How to explain the CPU; The CPU is commonly known as the Brains of a computer. Imagine Einstein as a juggler chef. He makes the sure the right things happen in the right order at the right time then tidies up after the job is done. (except for hard disks left fragmented my Microsoft Windows Operating System)

CPUs come in all kinds of strengths. Basically the higher the number, the more powerful and faster it is. You’ll find computers with dual core, quad core, octacore, i5, i7, processors, you get the idea.












Gigabytes (GB) megabytes (Mb)

Translate »