Do you really want me to tell the answer for that! It is like defining “what is a calculator?” after a child completes his/her mathematics homework, using the same. Without using a computer or without knowing what it is? You could not have come here.

Then why did I ask this question?

Let me put in a more practical way. Don’t define me in words; just point your finger towards your computer. Yes, I really mean it. It’s a simple game. Let’s play it.

If you have pointed your finger towards the monitor then you must read this 4 line story. Are you confused?

It really happened to me. Once I have gone to my dad’s office, when I was studying 6th standard. He asked me to move the computer aside. Can you guess what I did? I just moved the CRT monitor aside and said my dad that I had moved the computer. He just laughed at me and said, “Do you think that CRT monitor is the computer?”

So now, can you tell me what a computer is?

Yes! It’s the CPU. In general a computer should have a CPU, a monitor, keyboard, mouse, speakers etc. But when you mean it particularly, it’s the processor-motherboard assembly inside the cabinet.

Do you agree?

If not, then here is my justification. Whenever you’re pointing yourself, aren’t you pointing your chest! You could have pointed your hand on your leg or stomach, but why you’re not doing that? The reason is that without knowing yourself, you believe your heart is YOU. Similarly if you point your hand to the monitor, it is like pointing to your head. Have you ever done that after you have grown up?

If we go deeper, then it’s the processor and motherboard combo, which is mainly referred to as computer, because it’s responsible for the most part of the computing operations and it is the brain as well as heart of the computer.

You may ask me, if processor is the brain of a computer, then why a motherboard is called as motherboard? Because processor is like your brain and motherboard is like your body. Brain by itself cannot run everything, because it needs some sensors and tools for doing things such as to walk, see things, sing songs, it needs legs, eyes and mouth to do the corresponding things.

Likewise motherboard connects all part of the computer to its brain, the processor. It’s like the nervous system of our body. So motherboard can be compared to our heart, which is essential for proper function of our body.

Then, what are all the parts of the computer? First of all you need to interact with the computer. Initially, only keyboard was used to interact with computer. With the invention of graphical user interface, we started using mouse. And today, most of the computer users, mainly mid-aged people who learn computer newly, are using mouse, most of the time.

Why is output or display device so important? Just think, how you will feel if the person you’re interacting with is not replying you, after your consecutive messages, sent to them. Yes you got it right? So, you need some output or response from them. That’s why we have monitor and speakers.

With the advancement in computer technology, we started using touch screens, gamepad, gaming wheel, light pen etc., to interact with the computer. Also monitors have travelled a long way from CRT, LCD, LED and now they are 3D ready too. For presentations we even use projectors instead of monitors.

So, is it over with a computer?

No, it’s more. Basically computer is a multipurpose device. That’s why, it has a microprocessor. If it was meant for some particular application then there is no meaning in using a microprocessor, a microcontroller will do the job.

Are you wondering, why I have moved from computer to microcontroller? But before knowing, “What is microcontroller?” We should know what it’s not?

So let me tell you the basic difference between a microcontroller and a microprocessor. If we need a processor to do only a certain job, it’s better to go with microcontroller. Eg: Scientific Calculator. Because it doesn’t need huge memory, high processing speed etc., but what is needed then? Low power consumption, portability and low cost. So microcontroller has it all. It has a mini-microprocessor, very small RAM, small hard disk and some special communication ports, all built inside a single chip. So what’s the drawback here is, you cannot expand the memory or scale the processing speed easily.

Do you think why should you know this?

Our desktop computers are easily expandable. Because, you should know a fact that you can add more RAM, a discrete graphics card, USB 3.0 ports etc., easily. But can you do that in your basic mobiles?

So while buying a super-fast desktop computer, you need not have a huge investment at first. Buy with the budget you have at first and then add components later. But to add them later, you should have free slots in your motherboard.

So while buying a computer, don’t allocate the remaining available budget to motherboard, after buying all other components. You should always start with a processor and motherboard combo, while designing your computer configuration.

Till now I have not given any text book definitions about any computer parts, but I have written the title as “What is a Computer”? But one thing, what I’m sure is that after reading this blog post, you will play the game I mentioned in the beginning of the post with your friends, family or colleagues. So this is my approach. If you like my approach, you may read below.

This doesn’t end here.

You can get a practical knowledge about computer in just 6 weeks’ time. Yes! I really mean it. You don’t need to have any basic knowledge about computer, but after 40 days, you will be in a position to say

1.     How each and every computer components work – practical principle?

2.     How and where to buy the computer components?

3.     What to see before buying each component?

4.     Is your computer worth the money, you spent?