What is the internet?

People use it every day but how does it work?

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The internet is a global collection of computers that send messages to one another. In the early 1960s, computers were used only for special purposes, such as scientific research. There weren’t a lot of them because they were large and expensive. One computer and its accessories could easily fill an entire room. To exchange data, people would have to plan time to work together, and one computer would connect to another with a telephone call.

Building a network

The US government wanted a network that would allow computers to communicate even if some telephone lines were cut off. Suppose you wanted to send a message from Computer A to Computer B in each of three different types of networks. The first is a network with one central computer with all the others connected to it like the spokes of a wheel. The second is a network of several of these hub-and-spoke networks with their hubs connected. The third is a network where every computer is connected to several others, forming a kind of mesh. Which do you think would be most reliable if some computers and links were damaged?