From Wikipedia, the free encyclopedia.
The idea to build a free encyclopedia using the Internet can be traced at least to the late 1980s when it was suggested as part of several "Millennium Projects" including the United Nations University Millennium Project. Various names were suggested including "Encyclopedia Gaia", "Encyclopedia Terra", and although these projects did not proceed very far they kept the idea alive through the early 1990s, where they began to converge with Ted Nelson's ideas about hypertext and similar proposals from K. Eric Drexler.
In 1993, a project called Interpedia was being discussed; it was planned as an encyclopedia on the Internet to which everyone could contribute materials. The project never left the planning stage and it was overtaken by the explosion of the World Wide Web and the emergence of high-quality search engines.
The most profound output of these might be the early proposals, especially from the UNU MP in 1993, to filter the material for religious and ethical alignments that might make it easier to manage the divergence of values in any global project.
Anticipating major problems too early may have been one of the reasons these projects did not succeed. Converting existing material was less controversial.
A key branch of this activity is the digitization of old printed encyclopedias. In January 1995, Project Gutenberg started to publish the ASCII text of the Encyclopędia Britannica, 11th edition (1911), but disagreement about the methods halted the work after the first volume. In 2002, ASCII text of all 28 volumes was published on http://1911encyclopedia.org/ by another source; a copyright claim was added to the materials, but it probably has no legal validity. Other digitization projects have made progress on other titles. One example is Easton's Bible Dictionary (1897) digitized by the Christian Classics Ethereal Library. Probably the most important and successful digitization of an encyclopedia was the Bartleby Project's online adaptation of the Columbia Encyclopedia, Sixth Edition, 2000, which was put online at http://www.bartleby.com/65/ in early 2000 and is updated periodically.
Another related branch of activity is the creation of new, free contents on a volunteer basis. In 1991, the participants of the Usenet newsgroup alt.fan.douglas-adams  started a project to produce a real version of The Hitchhiker's Guide to the Galaxy, a fictional encyclopedia used in the works of Douglas Adams. It became known as Project Galactic Guide. Although it originally aimed to contain only real, factual articles, policy was changed to allow and encourage semi-real and unreal articles as well. Project Galactic Guide contains over 1700 articles, but no new articles have been added since 2000; this is probably partly due to the founding of h2g2, a more official project along similar lines.