The Internet

The internet is a global collection of interconnected networks. Because it is built by joining many separate networks together, it is often described as a network of networks.

Many networks, not one

Each network inside the internet is a working network in its own right, run by its own owner. Think of the network in your school, the network a payment company uses to connect card machines in shops, and the network a mobile phone company uses to connect its masts. They are separate systems, owned by separate organisations, yet data can pass from one to another.

They are linked by routers, devices that connect one network to another and pass data on between them. This is why the internet is not one enormous network owned or controlled by a single organisation, and why it has no single centre: it is many networks, joined together by routers.

Worked example: you join an online multiplayer game whose server sits in another country. Your data crosses your home network, then your broadband provider's network, then a national network run by a communications company, then the game company's network. Four different networks, four different owners, with routers handing the data along at each join.

One infrastructure, many services

The internet is only the infrastructure — the connected networks and the links between them. It carries data without caring what that data is for, in the same way a road carries any vehicle that fits on it.

Separate services run on top of that infrastructure, such as music streaming or online banking. The World Wide Web is just one of these services: the pages and sites you visit in a browser. Asking for a page sends a request across the internet, and the page travels back the same way.

So the web needs the internet, but the internet is not the web. The internet would still exist, and still carry other services, if the web had never been invented.