An encyclopedia or encyclopaedia, also (rarely) encyclopædia,Owing to differences in British and American English orthographic conventions, the spellings encyclopaedia and encyclopedia both see common use, in British-/Commonwealth- and American-influenced sources, respectively. The spelling encyclopædia – with the æ ligature – was frequently used in the 19th century and is increasingly rare, although it is retained in product titles such as Encyclopædia Britannica and others. The Oxford English Dictionary and Webster's Third New International Dictionary record both spellings: the former (1989) notes the æ would be obsolete except that it is preserved in works that have Latin titles, while the latter (1961-2002) notes that the digraph is rare in the U.S. Similarly, cyclopaedia and cyclopedia are rarely used truncations of the word originating in the early 17th century. is a comprehensive written compendium that contains information on all branches of knowledge or a particular branch of knowledge.
For a list of notable encyclopedias in history, see list of encyclopedias.
Encyclopedias :: Reference Tools
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Encyclopedia.com from Electric Library - Free resource offers more than 50,000 concise articles.
Meta Description: [ Free online encyclopedia - Search and browse 57,000 articles from the Columbia Encyclopedia and dig deeper with over 35 million articles from HighBeam Research ]
1911 Encyclopedia Britannica - Offers the 11th Edition Encyclopedia Britannica which is now in the public domain. All articles are searchable and alphabetized.
Meta Description: [ Online 1911 Encyclopedia Britannica. ]
Bartleby.com - Online publication of the Columbia Encyclopedia, Sixth Edition.
Meta Description: [ Columbia Encyclopedia, Sixth Edition, 2001-05 at Bartleby.com: the most up-to-date encyclopedia available on the web ]
Encyberpedia - Electronic encyclopedia with its own content as well as over 10,000 links to the best reference sites on the Internet.
Meta Description: [ Encyberpedia - The most complete summary of Encyclopedia reference information on the Internet---A 5 Star Site. ! ]
Encyclopaedia Britannica Online - Provides complete text of Encyclopaedia Britannica with search capabilities, related links, and multimedia enhancements. Free trial.
Meta Description: [ Encyclopedia Britannica Online, featuring the complete Encyclopedia Britannica, Britannica Concise Encyclopedia, Merriam-Webster's Dictionary & Thesaurus, videos, web sites, and magazines. ]
Encyclopedia FunTrivia - Thousands of categorized entries of trivia - an invaluable resource for answer seekers.
Encyclopedia Smithsonian - Links to on-line Smithsonian resources and answers to frequently asked questions from A to Z.
Meta Description: [ Encyclopedia Smithsonian, Links to on-line Smithsonian Resources and Answers to Frequently Asked Questions from Art to Zoo, Design, Crafts, Science, History, Technology, Biology, Astronomy, Dinosaurs, Birds, Quilts, Culture, Music, Politics, Geology, Planning a Visit ]
EncycloZine - Portal/concise encyclopedia offers fun activities for learning and exercising the mind. Daily articles introduce new topics in the arts, humanities, science, and technology, and provide links to related sites.
Meta Description: [ Articles and information on most topics in the arts, humanities, sciences, and technology. It also features games, puzzles, quizzes, mazes, and illusions ]
Free Internet Encyclopedia - 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.
How Stuff Works - Articles explain how hundreds of things work, from elements of the human body to space-age technology.
Meta Description: [ HowStuffWorks explains hundreds of subjects, from car engines to lock-picking to ESP, using clear language and tons of illustrations. We do the research so you don't have to. ]
Informationsphere.com - Free online encyclopedia that allows users to submit their own articles for inclusion in its database.
Meta Description: [ Free Encyclopedia: An online encyclopedia and search engine for terms and definitions. ]
Nuttall Encyclopædia of General Knowledge - Approximately 14,000 entries on topics including art, geography, literature, philosophy, religion. Originally published in 1907.
The LoveToKnow Free Online Encyclopedia - Browsable. Based on the eleventh edition of the Encyclopedia Britannica, first published in 1911.
Meta Description: [ LoveToKnow Free Online Encyclopedia - Over 35,000 in-depth entries on any subject ]
The Probert Encyclopaedia - Reference source with several hypertext linked entries covering a broad variety of subjects.
Meta Description: [ The Probert Encyclopaedia is a free online encyclopedia of over 235,000 references specialising in topics omitted by other encyclopedias ]
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Wikinfo - User edited encyclopedia based on Wiki software. Contains articles, information on editing, and a list of differences between this encyclopedia and Wikipedia.
Wikipedia - A free encyclopedia built collaboratively using Wiki software. (GNU Free Documentation License).
World Book Encyclopedia - Publisher site promoting sales of bound copies and offering link to online version.
Meta Description: [ The World Book web site offers a free encyclopedia, free dictionary, free atlas, homework help, study aids, and curriculum guides. World Book is publisher of the World Book Encyclopedia. ]
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.
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