Encyclopaedia Britannica Online Provides complete text of Encyclopaedia Britannica with search capabilities, related links, and multimedia enhancements. Free trial. http://www.britannica.com/ More Info
How Stuff Works Articles explain how hundreds of things work, from elements of the human body to space-age technology. http://www.howstuffworks.com/ More Info
Wikipedia A free encyclopedia built collaboratively using Wiki software. (GNU Free Documentation License). http://en.wikipedia.org More Info
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