Offers the 11th Edition Encyclopedia Britannica which is now in the public domain. All articles are searchable and alphabetized.

Encyclopedia provides around 100,000 articles on a variety of subjects and covers all topics.

Online publication of the Columbia Encyclopedia, Sixth Edition.

Electronic encyclopedia with its own content as well as over 10,000 links to the best reference sites on the Internet.

Provides complete text of Encyclopaedia Britannica with search capabilities, related links, and multimedia enhancements. Free trial available.

Thousands of categorized entries of trivia - an invaluable resource for answer seekers.

a comprehensive and easily accessible reference source for entrepreneurs that demand practical information that can be applied to their own business

Articles on various mysterious phenomena. Topics categorized into: afterlife mysteries, mediums, religious phenomena, secret societies, ghosts and phantoms and more.

Links to online Smithsonian resources and answers to frequently asked questions from A to Z.

Free resource offers more than 50,000 concise articles.

EncycloZine is a concise illustrated encyclopedic portal covering a wide range of topics in the arts, humanities, sciences, and technology. It also features games, puzzles, quizzes, and a multimedia gallery.

An encyclopedia composed of information available on the Internet. MacroReference contains references to large areas of knowledge, FAQs where available, and pointers to relevant areas of the MicroReference. MicroReference contains short bits of information and references to specific subjects.

Explains in details the manufacturing process of a wide variety of products, from daily household items to complicated electronic equipment and heavy machinery.

Articles explain how hundreds of things work, from elements of the human body to space-age technology.

Free online encyclopedia that allows users to submit their own articles for inclusion in its database.

Approximately 14,000 entries on topics including art, geography, literature, philosophy, religion. Originally published in 1907.

Descriptions of the people, places and things of Tolkien's Middle-earth in The Hobbit and The Lord of the Rings.

Browsable. Based on the eleventh edition of the Encyclopedia Britannica, first published in 1911.

Reference source with several hypertext linked entries covering a broad variety of subjects.

User edited encyclopedia based on Wiki software. Contains articles, information on editing, and a list of differences between this encyclopedia and Wikipedia.

Free volunteer-edited encyclopedia with over 200,000 articles.

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.

Offers in-depth information on a variety of subjects and educational activities for children.