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World66 was a Dutch company which embraced the open content idea and tried to transform it into a profitable business. It is now owned by El Segundo, California, based Internet Brands, Inc which acquired it in April 2006.
The site was founded in 1999 by Richard Osinga and Douwe Osinga as Osinga.com, but the name was changed to World66 in the same year. On November 29, 2003, it expanded by absorbing the travel-related CapitanCook wiki. Internet Brands announced their acquisition of World66 on April 20, 2006. 
World66 uses wiki-like software based on the Zope application server, which allows everyone to add or edit contents. The site claims more than 80,000 travel related articles covering about 10,000 destinations around the world and all of them are licensed under the Creative Commons Attribution-ShareAlike 1.0 Licence.
In 2004, World66 relicensed all content to an open license first a GNU FDL license and consequently to CC by-sa 1.0 - those who had contributed under GNU FDL license were informed of the change by e-mail and had the possibility to withdraw contributions.