What is the Internet and how does it work? How do computers and smartphones communicate with one another?

Sian Bayley

It has become ingrained in our daily lives – we use it to work, shop, and chat with friends, but how many of us understand how the internet actually works?

Amali de Alwis, CEO at Code First: Girls, a charity which helps young women and girls learn coding for free says: "It's crucial for all of us to understand the basics of how tech and the internet works, because the internet isn't just for 'techies' anymore, it's infrastructure that affects us all.

“Without a basic understanding, it's harder for us to understand how decisions made about the internet will impact us, or query who has power or control. This is especially important now as this is now the most important way that we communicate, get news and entertainment, shop, learn, and work."

Future London takes a look at severs, IP addresses and packages to help you understand the internet.

(PA Archive/PA Images)

What is the internet?

The internet is a wire buried in the ground – surprisingly analogue, right? It can be fibre optics or copper, but is occasionally beamed through satellites and mobile phone networks.

Computers that are directly connected to the internet can communicate with each other and send and receive information.

Is my computer directly connected to the internet?

No – your home computer or mobile is a client which is indirectly connected to the internet through an internet service providers like BT, Virgin Media, or TalkTalk.

The only computers that are connected to the internet are called servers. Servers have the pages from websites saved as files on their hard drives.

How does the internet work?

When you want to visit a website, your device goes through your internet service provider to the internet, where you can connect to the server of the website you want to visit.

Every server has a unique Internet Protocol address or IP address. It works a bit like a postcode and helps different computers find each other.

The internet functions by sending requests and receiving information from your device to a server.

How do computers talk to each other?

Code First: Girls have written a simple explanation as part of the Duke of York’s iDEA programme, which helps users develop their digital skills online for free and win badges. They explain that when you open a webpage or file on the internet you are sending a request to a web server. The request is broken down into smaller chunks of computer data known as ‘packets’ to avoid congestion in network traffic.

More information is added to the packets to help them get to the destination computer and reassemble correctly. This must include:

  • The source - location of the computer sending the packets
  • The destination - location of the computer receiving the packets
  • The packet sequence - containing instructions on how the packets should be reassembled to convey a message or image.
  • Data - the contents of our message represented as computer data
  • Error check – checking message has been sent correctly

The computers must then ‘shake hands,’ which is a term used to describe how the computer sending the packets and the computer receiving them must establish a reliable connection to make sure they can be sent without any problems.

Once they have shaken hands, they can exchange packets, which is known as ‘packet switching’.

The packets travel to their destination through allocated computer ports with the help of a router. Routers help computers handle packets through ports, which co-ordinate and distribute packets like a post office sorts through post.

When the packets have been transferred they are reassembled in their original form – allowing the destination computer to display (or ‘render’) the message. And the whole process takes less than a second