World Book Encyclopedia Online version of the complete reference work along with dictionary, atlas, links, magazines, historical documents, audio, video, images, and 3D photographs. Requires free temporary registration with option to buy continued access for full articles.
The Probert Encyclopaedia Reference source with several hypertext linked entries covering a broad variety of subjects.
Encyberpedia Electronic encyclopedia with its own content as well as over 10,000 links to the best reference sites on the Internet.
Encyclopedia Smithsonian Links to on-line Smithsonian resources and answers to frequently asked questions from A to Z.
How Stuff Works Articles explain how hundreds of things work, from elements of the human body to space-age technology.
HighBeam Encyclopedia Free resource offers more than 50,000 concise articles from the Columbia Encyclopedia.
Wikinfo User edited encyclopedia based on Wiki software. Contains articles, information on editing, and a list of differences between this encyclopedia and Wikipedia.
1911 Encyclopedia Britannica Offers the 11th Edition Encyclopedia Britannica which is now in the public domain. All articles are searchable and alphabetized.
Encyclopaedia Britannica Online Provides complete text of Encyclopaedia Britannica with search capabilities, related links, and multimedia enhancements. Full text for subscribers only; free trial available.
Nuttall Encyclopædia of General Knowledge Approximately 14,000 entries on topics including art, geography, literature, philosophy, religion. Originally published in 1907.
Bartleby.com Includes the Columbia Encyclopedia, Sixth Edition, dictionaries, thesauri, and more.
MSN Encarta Encyclopedia Online home of the Encarta encyclopedia, world atlas, dictionary, thesaurus, multimedia collection, and homework tools.
Hutchinson Encyclopedia "A subset of the content (concise set) is provided for free, the access to the rest of the Hutchinson Encyclopedia requires subscription."
Wikipedia A free encyclopedia built collaboratively using Wiki software. (GNU Free Documentation License) and with over 1,000,000 articles. Note that because articles can be "vandalized," information on Wikipedia is not always accurate.
