Wikibooks, previously called Wikimedia Free Textbook Project and Wikimedia-Textbooks, is a project of Wikimedia Foundation, initiated on July 10, 2003. Wikibooks is the home for Wikijunior.
The project is a collection of free textbooks and manuals. You can edit any book module right now by clicking on the edit this page link that appears in every Wikibooks module.
The project was opened in response to a request by Karl Wick for a place to start building open content textbooks such as organic chemistry and physics in order to bring education to humanity and reduce the costs and other limitations to top-quality learning materials. It was started on July 10, 2003 and has been growing steadily since. As a result of the continuous growth, Wikibooks was split into several language-specific subdomains on July 21, 2004.
All of the site's content is covered by the Creative Commons Attribution-ShareAlike 4.0 license. Some of the first books were completely original and others began as text copied over from other sources of textbooks found on the Internet. Contributions remain the property of their creators, while the copyleft licensing ensures that the content will always remain freely distributable and reproducible. See copyrights for more information.
The site is working towards completion of several complete textbooks, which will eventually be followed by mainstream adoption and use of texts developed and housed there. Printable PDF versions can now be generated on-the-fly, and PediaPress provides print-on-demand services. The Wikimedia Foundation's press release has more details.
Note: This list includes closed wikis. The following Wikibooks projects are closed: aa, ak, als, as, ast, ay, ba, bi, bm, bo, ch, co, ga, gn, got, gu, kn, ks, lb, ln, lv, mi, mn, my, na, nah, nds, ps, qu, rm, se, simple, su, sw, tk, ug, uz, vo, wa, xh, yo, za, zh-min-nan, zu (44 total). This list also includes locked wikis, such as ang and ie.