Serendipity35

Wikibooks is a collection of free textbooks, manuals, and other texts that are written collaboratively online. Since the is a wiki, anyone can edit book modules without their contributions being subject to review before modifications are accepted. The project was opened in response to a request by Wikipedia's Karl Wick for a place to start building open-content textbooks. It was suggested that initial efforts might be directed towards titles such as organic chemistry and physics in order to reduce the costs and other limitations on learning materials.

Some books are original, others began as text copied over from other free-content textbooks found on the Internet. All of the site's content is covered by the GNU Free Documentation License. Like Wikipedia, contributions remain the property of their creators, while the copyleft licensing ensures that the content will always remain freely distributable and reproducible.

Wikijunior is the working title for a set of books targeted to children aged 8–11. This subproject of Wikibooks will be both a website and magazine. The website is currently in development in English, Japanese and Danish, but expected to be in at least a dozen languages.

Wikiversity is another offshoot of Wikibooks, though it ultimately may be to large to be considered a "subproject" of Wikibooks. It's an attempt to build a free, open learning environment and research community. People are building online courses as a form of co-operative and interactive exchange of knowledge. Wikiversity currently has portals in 17 different languages.