16.4 The network
The term 'network' is used to describe some very different interconnected systems. In a home setting, you might have just two computers linked together to share documents and devices (such as a printer and a scanner) and to use the same internet connection. This setup is a network, albeit a small one. At the other end of the scale is a multinational company with a network of computers distributed all over the world.
A network belonging to a single organisation, where the computers are close to each other on a single site, is known as a Local Area Network or LAN. In a Wide Area Network, or WAN, the computers may be spread over a large geographic area such as a city, a country, or even across continents. The computers in a WAN are usually linked via private communication links leased by the organisation.
When your computer is connected to a network, you have access to network resources such as shared printers and software, and to data and possibly storage space on other computers. A network can also support email and other communication services for its users.
The checkout terminals in a supermarket will almost certainly be linked to each other in a LAN within the building. There will probably also be links to other networks within the supermarket organisation. For example, there will be links to a network at the head office which may be many hundreds of miles away.
Activity 15 (exploratory)
Have another look at what you have just read about networks. Write two or three sentences to explain the advantages of networked computers.
You may have mentioned advantages such as sharing documents, devices and an internet connection in a small-scale network. In a larger network, resources such as software applications, data and printers could be shared, and access provided to an email service.