The articles can be freely
redistributed and reused under a Creative Commons license,
including for translations, as long as the author(s) and source
are cited. PLoS also launched PLoS ONE, an online forum meant
to publish articles on any subject relating to science or
medicine.

Three years after the beginning of PLoS as a publisher, PLoS
Biology and PLoS Medicine have had the same reputation for
excellence as the leading journals Nature, Science and The New
England Journal of Medicine. PLoS has received financial
support from several foundations while developing a viable
economic model from fees paid by published authors,
advertising, sponsorship, and paid activities organized for
PLoS members. PLoS also hopes to encourage other publishers to
adopt the open access model, or to convert their existing
journals to an open access model.

# Wikipedia

Wikipedia was launched in January 2001 by Jimmy Wales and Larry
Sanger (Larry resigned later on). It has quickly grown into the
largest reference website on the internet, financed by
donations, with no advertising. Its multilingual content is
free and written collaboratively by people worldwide, who
contribute under a pseudonym. Its website is a wiki, which
means that anyone can edit, correct and improve information
throughout the encyclopedia. The articles stay the property of
their authors, and can be freely used according to the GFDL
(GNU Free Documentation License).

In December 2004, Wikipedia had 1.3 million articles (by 13,000
contributors) in 100 languages. In December 2006, it had 6
million articles in 250 languages. In May 2007, it had 7
million articles in 192 languages, including 1.8 million
articles in English, 589,000 articles in German, 500,000
articles in French, 260,000 articles in Portuguese, and 236,000
articles in Spanish.

Wikipedia is hosted by the Wikimedia Foundation, founded in
June 2003, which has run a number of other projects, beginning
with Wiktionary (launched in December 2002) and Wikibooks
(launched in June 2003), followed by Wikiquote, Wikisource
(texts from public domain), Wikimedia Commons (multimedia),
Wikispecies (animals and plants), Wikinews, Wikiversity
(textbooks), and Wiki Search (search engine).

# Citizendium

Citizendium was launched in October 2006 as a pilot project to
build a new encyclopedia, at the initiative of Larry Sanger,
who was the cofounder of Wikipedia (with Jimmy Wales) in
January 2001, but resigned l