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An encyclopedia (alternatively encyclopędia) is a written compendium of human knowledge.

The term comes from the Greek words εγκύκλιος παιδεία, enkyklios paideia ("in a circle of instruction"). From εγκύκλιος, circuit shaped from κύκλος circuit and παιδεία, meaning instruction. See the Note on spelling below.

Encyclopedias can be general, containing articles on topics in many fields (the Encyclopędia Britannica is a well-known example), or they can specialize in a particular field (such as an encyclopedia of medicine or philosophy). There are also encyclopedias that cover a wide variety of topics from a particular cultural or national perspective, such as the Great Soviet Encyclopedia.

Encyclopedic works have been produced throughout much of human history, but the term encyclopedia was not used to refer to such works until the 16th century.

Table of contents
1 Early encyclopedic works
2 Note on spelling
3 Notable encyclopedists before 1700
4 External links

Early encyclopedic works

Many writers of antiquity (such as Aristotle) attempted to write comprehensively about all human knowledge. Although John Harris is often credited with establishing the now-familiar encyclopedia format in 1704 with his Lexicon technicum the English physician Sir Thomas Browne specifically employed the word encyclopaedia to describe his compendium of refuted Vulgar Errors also known as Pseudodoxia Epidemica as early as 1646 (6th edition 1676) . The venerable Encyclopędia Britannica had a modest beginning: from 1768 to 1771 three volumes were published. Perhaps the most famous early encyclopedia was the French Encyclopédie, edited by Jean Baptiste le Rond d'Alembert and Denis Diderot and completed in 1772 (28 volumes, 71,818 articles, 2,885 illustrations).

The encyclopedia's hierarchical structure and evolving nature is particularly adaptable to a disk-based or on-line computer format, and all major printed encyclopedias had moved to this method of delivery by the end of the 20th century. Disk-based (typically CD-ROM format) publications have the advantage of being cheaply produced and extremely portable. Additionally, they can include media which is impossible in the printed format, such as animations, audio and video. Hyperlinking between conceptually related items is also a significant benefit. On-line encyclopedias offer the additional advantage of being (potentially) dynamic: new information can be presented almost immediately, rather than waiting for the next release of a static format (as with a disk or paper based publication).

Information in a printed encyclopedia necessarily needs some form of hierarchical structure, and traditionally the method employed is to present the information ordered alphabetically by the article title. However with the advent of dynamic electronic formats the need to impose a pre-determined structure is unnecessary. Nonetheless, most electronic encyclopedias still offer a range of organisational strategies for the articles, such as by subject area or alphabetically.

This article is part of the Wikipedia, which is in itself an encyclopedia.

Note on spelling

None of the spellings, encyclopedia, encyclopaedia, or encyclopędia is formally a misspelling. Historically, however, the latter two represent a very old spelling mistake. According to the Oxford English Dictionary, the spelling with the ae or ę is "pseudo-Greek" and "an erroneous form (said to be a false reading) occurring in MSS. of Quintilian, Pliny, and Galen". The Oxford English Dictionary notes that the ę is not found in the original Greek enkyklios paideia for "encyclical education", described as "the circle of arts and sciences considered by the Greeks as essential to a liberal education".

The Oxford English Dictionary asserts that the spelling with ę "has been preserved from becoming obsolete by the fact that many of the works so called have Latin titles, as Encyclopędia Britannica". That particular encyclopedia includes the ligature form ę in its official name.

At least half the citations in the Oxford English Dictionary are for the so-called "incorrect" spelling. Neither the Oxford English Dictionary nor Webster's Third New International Dictionary states a preference, although the British Oxford English Dictionary puts the ę form first, and the American Webster's puts it second.

See list of encyclopedias for links to specific encyclopedias.

See also: History of Science and Technology, Encyclopedist, Library and Information Science, Literature, Lexicography, dictionary, Reference work, Pauly-Wissowa

Notable encyclopedists before 1700

External links