Wikipedia is a wiki-based free content encyclopedia with supporting almanac-like and gazetteer-like information. Free means both free to use and free to edit. Wikipedia is multilingual, and an open-content, collaboratively developed creation, managed and operated by the non-profit Wikimedia Foundation. As of January 2004, it contains over 190,000 articles in English, and nearly 200,000 articles in other languages.

Wikipedia started as an English language project on January 15, 2001. Later projects were begun to build Wikipedia in other languages.

Table of contents
1 Essential characteristics
2 Vandalism
3 Policies
4 Personnel
5 History
6 Software and hardware
7 Antecedents
8 Sister projects
9 Similar projects
10 Downloading the database
11 Distribution of contents
12 Wikipedia 1.0
13 External links

Essential characteristics

There are three essential characteristics of the Wikipedia project, which together define its niche on the World Wide Web:

  1. It is, or aims to become, primarily an encyclopedia.
  2. It is a wiki, in that (with a few exceptions) it can be edited by anyone.
  3. It is open content, and uses the copyleft GNU Free Documentation License.

If you wish to become a Wikipedia contributor, please take a look at the page titled Welcome to newcomers.


One pertinent issue on Wikipedia is "
vandalism": silly or offensive edits to its encyclopedia articles. For example, Sarah Lane, presenter of "Sarah's Blog Report," part of The Screen Savers TV program from TechTV, "vandalised" the Wikipedia page on monkeypox, while on air, by writing "Sarah Lane is totally cool and does not have monkeypox." She later wrote that "Although this excites me in its ease and simplicity, it's a little frightening. I mean, what if I had instead written 'My boss is a big fat **** and his phone number is ****'? Sure, somebody would delete it, but this calls for some seriously dedicated moderators."

"Because Wikipedia is a radically free, open project, it attracts an anarchistic element," Larry Sanger, co-founder of Wikipedia, admitted to Wired News. "Fortunately, most of us are willing to take a definite stand against vandalism ... and to get rid of it instantly."


Wikipedia's participants commonly follow, and enforce, a few basic policies.

First, because there is a huge variety of participants of all ideologies, and from around the world, Wikipedia is committed to making its articles as unbiased as possible. The aim is not to write articles from a single objective point of view -- this is a common misunderstanding of the policy -- but rather, to fairly present all views on an issue, attributed to their adherents.

Second, there are a number of article naming conventions; for example, when several names exist, the most common one in the respective Wikipedia language is to be used.

Third, Wikipedians use "talk" pages to discuss changes to the text, rather than discussing the changes within the text itself. Concerns which seem to span many articles may require a more general treatment at Meta-Wikipedia or on the mailing lists.

Fourth, there are a number of kinds of entries which are generally discouraged, because they do not, strictly speaking, constitute encyclopedia articles. For example, Wikipedia entries are not dictionary definitions, and the wholesale addition of source material such as the text of laws and speeches is generally frowned upon.

Fifth, there are a variety of rules that have been proposed and which have varying amounts of support within the Wikipedia community. The most widely supported rule is: "If rules make you nervous and depressed, and not desirous of participating in the wiki, then ignore them entirely and go about your business." When these proposed rules are violated, it is decided on a case by case basis among Wikipedians whether they should be more strictly enforced or not.


Wikipedia has been edited by thousands of people. Wikipedia calls people who edit it Wikipedians. The total number of edits approximately doubled between January 2002 and January 2003, from 1,000 a day to 2,000 a day.

There is no editor-in-chief, as such. The two people who founded Wikipedia are Jimmy Wales (CEO of the small Internet company Bomis, Inc.) and Larry Sanger. For the first thirteen months, Sanger was paid by Bomis to work on Wikipedia. Sanger was said to have taken a role of mediator at times, making decisions on issues of heated debates. This was based not on formal authority, but on demands from users at large. Funding ran out for his position, leading to his resignation in February of 2002. Other current and past Bomis employees who have done some work on the encyclopedia include Tim Shell, one of the co-founders of Bomis, as well as programmers Jason Richey and Toan Vo.


Wikipedia has been in continuous operation since January 10, 2001. See History of Wikipedia for more.

Software and hardware

The particular version of wiki software that originally ran Wikipedia was UseModWiki, written by Clifford Adams ("Phase I"). First it required CamelCase for links; soon it was also possible to use the current linking method with double brackets. In January 2002, Wikipedia began running on PHP wiki software, which used an underlying MySQL database, added many features (and abolished the behaviour of CamelCase words automatically becoming links), and was specifically written for the Wikipedia project by Magnus Manske ("Phase II"). After a while, the site started to slow down to an extent where editing became almost impossible; several rounds of modifications to the software provided only temporary relief. Then Lee Daniel Crocker rewrote the software from scratch; the new version, a major improvement, has been running since July 2002; this "Phase III" software is now also called MediaWiki. Brion Vibber has since taken the lead in fixing bugs and tuning the database for performance.

In late 2003, server outages had become a serious problem to Wikipedia contributors. Many of them reported they had difficulty editing articles by getting time-outs and severe slowness. This was due to congestion on the single server that was running all the Wikipedias at the time.

The project runs on a set of three dedicated servers, located in San Diego. There is currently a single database server, and two front-end web servers run the front-end software, performing page rendering for all the Wikipedias. To increase speed further, rendered pages for anonymous users are cached in a filesystem until rendered invalid, allowing page rendering to be skipped entirely for most common page accesses.


The idea to collect all of the world's knowledge within arm's reach under a single roof goes back to the ancient Library of Alexandria and Pergamon.

The Chinese emperor Yongle oversaw the compilation of the Yongle Encyclopedia, one of the largest encyclopedias in history, which was completed in 1408 and comprised over 11,000 handwritten volumes, of which only about 400 now survive.

The early Muslim compilations of knowledge in the middle ages included many comprehensive works, and much development of what we now call scientific method, historical method, and citation. Notable works include Fakhr al-Din Razi's encyclopedia of science, the Mutazilite Al-Kindi's prolific output of 270 books, and Ibn Sina's medical encyclopedia, which was a standard reference work for centuries. Also notable are works of universal history (or sociology) from Asharites al-Tabri, al-Masudi, al-Athir, and Ibn Khaldun, whose Muqadimmah contains cautions regarding trust in written records that remain wholly applicable today. These people had an incalculable influence on methods of research and editing, due in part to the Islamic practice of isnah which emphasized fidelity to written record, checking sources, and skeptical inquiry.

However, these works were rarely available to more than specialists: they were expensive, and written for those extending knowledge rather than (with some exceptions in medicine) using it. The modern idea of the general purpose widely distributed printed encyclopedia goes back to just a little before Denis Diderot and the 18th century encyclopedists. Major university libraries can be seen as museums of monumental encyclopedic endeavors in various countries. Frequently found titles are the English Encyclopędia Britannica, the Spanish Enciclopedia Universal Illustrada, the German Meyers Konversations-Lexikon and Brockhaus. See encyclopedia for more information.

The idea to use automated machinery beyond the printing press to build a more useful encyclopedia can be traced to H. G. Wells's short story of a World Brain (1937) and Vannevar Bush's future vision of the microfilm based Memex, in As We May Think (1945). An important milestone along this path is also Ted Nelson's Project Xanadu (1960).

With the development of the Internet, many people attempted to develop online encyclopedia projects. See History of Internet encyclopedia projects. Free software exponent Richard Stallman articulated the usefulness of a "Free Universal Encyclopedia and Learning Resource" in 1999. He described Wikipedia's formation as "exciting news," and his Free Software Foundation encourages people "to visit and contribute to the site."

Sister projects

Wikipedia has following sister projects:

  • Wiktionary, a free dictionary project
  • Wikibooks, a free textbook project
  • Wikiquote, a free encyclopedia of quotations
  • Wikisource, a repository of source texts in any language which are either in the public domain or are released under the GFDL.

Similar projects

Wikipedia has been occasionally compared to the following collaborative online projects:

  • Nupedia, a slow-moving project to produce a free peer reviewed encyclopedia.
  • Everything2 has a wider range and does not exclusively focus on building an encyclopedia; its contents are not available under a copyleft license.
  • Indymedia, which focuses on networking first-hand source material from local, diverse groups of people around the world, linking grassroots, non-virtual social reality and the internet community.
  • H2G2, a collection of sometimes humorous encyclopedia articles, based on an idea from Douglas Adams's The Hitchhiker's Guide to the Galaxy. Articles are not freely redistributable.
  • EvoWiki is "a Wiki about evolution and origins. The focus is on evolution education, particularly addressing the arguments of Creationism and Intelligent Design from the perspective of mainstream science. It is inspired by webpages such as and, and the goal of EvoWiki is to complement rather than duplicate these online resources". (source)
  • Disinfopedia, a project to expose propaganda and paid spin doctors.
  • Consumerium, a project to provide consumers with product information and increase the power of the consumer in a market economy.
  • Wikitravel, a free travel guide started in July 2003.
  • Planetmath is a free Wiki-style mathematical encyclopedia which was originally built to replace Mathworld, a propriatery system hosted at Wolfram Research which was down for some time due to legal difficulties. Since Mathworld has returned, Planetmath has still thrived. See Planetmath's site.

Downloading the database

If people want to use Wikipedia's
open content for something that cannot best be done on Wikipedia, they may at any time download a nearly-current version of the entire article database to use for any purpose, within the terms of the GFDL.

Distribution of contents

Websites containing what is essentially a direct copy of the Wikipedia articles:

English version:

German version:

French version:

Japanese version:

Dutch version:

Spanish version:

Since information about them is especially useful when Wikipedia is down, visit Copies of Wikipedia content to learn more.

Wikipedia 1.0

Wikipedia 1.0 is a proposed version of the Wikipedia content on CD-ROM and paper.

External links


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