Directory of Encyclopedias Resources

Online encyclopedias which are released under open-content licenses or are freely distributable.

Subcategories

Citizendium

http://en.citizendium.org/
Wiki encyclopedia project in which authors use their real, verified names and recognized subject experts can guide the development of citable articles.
Connected: An Internet Encyclopedia

http://www.freesoft.org/CIE/
The engineering, theoretical concepts, and organizations of the Internet (freely distributable).
Ekopedia

http://www.ekopedia.org/
Ekopedia is an encyclopedia about alternative life techniques with strong focus on ecological impact.
Everything2

http://www.everything2.com/
An extensively hyperlinked collection of facts, ideas, notes and humor to which anyone can add.
Open Site

http://open-site.org/
A volunteer-run open content encyclopedia.
PlanetMath

http://planetmath.org/
Collaborative, peer-reviewed mathematics encyclopedia with TeX input, inspired by MathWorld (GNU Free Documentation License).
SklogWiki

http://www.sklogwiki.org/
An open wiki for statistical mechanics and thermodynamics.
Wikipedia Article - Nupedia

http://en.wikipedia.org/wiki/Nupedia
Nupedia was a public peer-reviewed general encyclopedia created by volunteer scholars, with resources for readers and contributors (GNU Free Documentation License). It can be considered to be Wikipedia's direct ancestor.

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