The Internet and the Web
Kinds of network
Tell a network that covers one site from one that stretches between towns, and say what joined-up computers can do that separate ones cannot.
A network is computers joined up so that they can pass things to each other: files, messages, and work sent off to a printer. Nothing about the joining says how big it has to be or how far it has to go — those are the two things that change from one network to the next, and they are what networks are usually named after.
Near and far
Networks are usually described by the distance they cover. One that stays inside a single building or site — a lab, an office, a home — is called local. One that stretches between towns or countries is called wide. The words describe distance and nothing else — not how many machines are involved, not how fast the link is, and not who owns it.
Worked example
A school has 30 computers in a lab. Before the network was put in, each one had its own printer. What changed when they were joined?
Count what the school needed before: thirty computers, thirty printers.
Counting the before-state is what makes the saving visible rather than something you are asked to believe.
Try it together
Now think this one through: a company has an office in Mumbai and an office in Pune, and every machine in both can reach every other.
Work out which kind of network each part of the description is.
1.The machines inside the Mumbai office are joined to each other. Does that part stay inside one site? Answer yes or no.
Have a go
Have a go on your own. A library has one machine holding all its book records, and eight desks that can look records up. What has the network given the library?
Ready to practise?
Eight questions on what you have just read. Nothing is timed, and you can play as many times as you like.