What is a Network?

In this lesson we will learn the basics of what is a computer network.

In the early days of personal computing computers were usually disconnected from one another. They would be used for document writing and calculations, and special equipment was required to connect them together.

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Nowadays nearly all computers come with network equipment included so it is easy to join them in a network.

How are networks formed?

Network

Normally a network is controlled by a central link. Sometimes this central link is another computer. Usually in a home it is a small box called a router. This router is a specialised computer.

The computers can be connected to the router through physical cables or through wireless signals.

Normally the router requires a password from each computer. This is for security so only trusted computers can access the network.

Once computers are on the same network they can share information with one another.

For example, you can copy documents and pictures from one computer to another. When this happens the documents are sent over the network connection to the router, which then sends the data to the destination computer.

All data passed over the network is known as network traffic. The router is like a traffic policeman that directs this traffic down the correct paths.

Another benefit to connecting computers together on a network is that they can share their connection to the internet.

The internet is a ‘network of networks’ – it is the network that connects computers from all over the world.

There is no one central router for the internet: there is far too much traffic for just one router to cope with! So the internet is a decentralised network: because there is no centre.

If a router on a home network is connected to the internet then all of the computers on that network can connect to the internet through the router. This is how most homes have their internet connection nowadays.