If you bought a computer a few years ago, it would invariably come with a free CD-Rom encyclopedia. At the time it seemed like a life-changer, but after an hour or two spent looking at ancient wildlife clips and a timeline about the Romans, the excitement wore off. Today’s internet equivalents are bigger, faster and more interactive, whether you’re helping youngsters with their homework or cramming for the pub quiz.

1 nationalgeographic.com
The American magazine covers a huge range of subjects, from space and the environment to animals and even world music (where you can listen to thousands of artists). What’s shared is a passion for the living world. Inspiring stuff, brilliantly presented.

2 www.nasa.gov
Videos, podcasts, a vast photo archive, 3-D image files and pages for missions where you can view raw data as they stream in, make this a must for anyone with even a fleeting interest in space.

3 howstuffworks.com
Expertly written articles explaining everything under the sun, from how a Taser is put together to the history of the jeep. Hundreds of videos add to the experience.

4 discovery.com
It might be a giant plug for the Discovery Channel’s roster of shows, but the dozens of microsites here are uniformly excellent. Links to the websites of sister channels (Military, Science and more) drive an even bigger wedge between you and any work you might have been thinking of doing.

5 smithsonianmag.com
The Smithsonian Institution in Washington is the world’s largest museum complex, and its magazine is a rival to National Geographic. The associated website is a rich source of eye-opening good reads.

6 bbc.co.uk/nature
Possibly the best BBC microsite — a simple collection of video clips. Choose from 370 animals to see related footage, and scare your friends when they walk in by playing the “what they sound like” widget. (Works better with tigers than rabbits.)

7 ted.com
TED is an organisation that invites inspirational people to an annual conference to share their thoughts on the world, technology, design and more. It videos the results and archives them here. Will keep you hooked for days.

8 arkive.org
Videos and photos that live up to the simple tagline “images of life on earth”. Endangered species are a speciality; the promise is they will live on here if nowhere else.

9 historytoday.com
Once registered for free, you can browse through hundreds of articles culled from the popular magazine. They are sorted into categories and, despite the lofty academic credentials of the authors, are easily readable.

10 pbs.org
PBS is a publicly funded American TV channel with an emphasis on science, the arts and history. Watch entire shows or browse their excellent, richly detailed sites.

Got a subject you’d like to see covered? E-mail us at topten@sunday-times.co.uk

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