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Hello guys,

All of us, regardless our age, are familiar with the internet and we often use it during the day. We use it to catch up with the latest news, to have fun, to communicate, to work etc. It seems that there are only a few things which we can’t do using the internet. Given that it offers all those to us, we could say that it seems a little magic. Just think if one man from the previous century could see us. He would consider our mobile to be a result of magic, something like a magic wand, and our computer an advanced magic sphere.

But, what is the internet? Believe me there is nothing magic in that.

The internet is a compound word. It derives from the words Inter and Net.

What is the net though? Since we refer to computers let’s talk about a computer network. A computer network so, is when 2 or more computers can connect to each other, usually with cables, and exchange files and information. This connection between computers is simple and is usually made by using a device called switch. In a local network, just like the one you see, every computer can communicate, for example transfer files, with another by using cables and the switch.

There are thousands local networks, like this one, globally. People connect their computers, not only because they want to communicate and exchange files but also to share devices and services which can be provided by one computer of the network. For example, if one computer is connected to a printer in a local network, because of this connection between the computers, all the other computers can print too.

Think now of what would happen if all these networks could connect to each other! In this way, a computer which belongs to a local network in Greece would be able to connect to a computer in India and exchange files. In this case, all the local networks connect to each other and create a huge computer network, the internet. However, how is that connection made and by the use of which cables? The cables which have been used for years are the telephone cables. Just as we can call someone in India, in the same way, a computer can connect to another computer anywhere in the world.

And that is the internet. A huge computer network. To make this network connection happen, we must replace the switch of every local net with the Router. The router can still has the role of the switch, which means it connects the computers of a local network but also does multiple tasks which allow that connection between the networks.

Switches create a network. Routers connect networks.

So, the internet is the connection between computers. The computers connect to each other and exchange information and files.

Let’s understand that better with an example. One, amongst the many ways we can use the internet, is to visit a webpage. Let’s see what happens in that case.

A webpage is a file like the ones we have in our computer folders. It also lies in a folder on another computer. Let’s say that we want to visit the webpage www.facebook.com. This webpage, as we mentioned, is a file, in another folder, on a computer which is placed in the building of a company called “Facebook”.

To succeed in displaying this webpage on our computer we open a browser and type the address. When we press ENTER, our computer will connect to the facebook computer which contains this webpage and will ask of a copy. The facebook computer, after dividing the webpage in small packets, will send them to our computer through the connection cables. The packets will reattach, creating again the webpage on our computer.

So, when we see the webpage on our computer, it is indeed on it since it reached our computer mainly through the telephone cables which were used to make the connection between the computers.