
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?
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M.G. Leonard
Meet the bug-crazy children's author whose love of nature began with reading.

A "BOOMLESS" CRUISE
For the first time in 22 years, a civilian (non-military) aircraft has broken the sound barrier.

THE WORLD'S WEIRDEST MUSEUMS
Jenny Ackland takes a whirlwind tour of some of the oddest exhibitions on the planet.

Skydiving salamanders grip with toes
A new study has found that wandering salamanders pump blood in and out of their toes to help them grip.

Searching for Planet X
Is there an undiscovered planet playing hide-and-seek beyond Neptune?

TOUGH TADPOLES
This picture shows a swarm of western toad tadpoles in a lake in Vancouver Island, off the coast of Canada.

People wiggle ears to hear
Can you wiggle your ears? Itâs a trick only some people can do, but it turns out that the muscles used to do it also activate when humans are trying to listen to something.

Ancient scroll decoded
Scientists have found a way to âdigitally unrollâ a scroll that was burnt to a crisp nearly 2,000 years ago.

Could we use volcanoes to make electricity?
Find out if people could tap into Earth's fiery depths to generate energy.

Wildlife watch
As spring begins, Jenny Ackland shows you how to experience nature waking up.