Nupedia, a multi-language online encyclopedia, is launched.

Nupedia was a multi-language online encyclopedia whose articles were written by volunteer contributors with relevant subject-matter expertise, reviewed by expert editors before publication, and licensed as free content. It was founded by Jimmy Wales and underwritten by Bomis, with Larry Sanger as editor-in-chief. Nupedia operated from March 2000 until September 2003. It is best known today as the predecessor of Wikipedia. Nupedia had a seven-step approval process to control content of articles before being posted, rather than live wiki-based updating. Nupedia was designed by a committee of experts who predefined the rules. It had only 21 articles in its first year, compared with Wikipedia having 200 articles in the first month, and 18,000 in the first year.

An online encyclopedia, also called an Internet encyclopedia, is a digital encyclopedia accessible through the Internet. Some examples include pre-World Wide Web services that offered the Academic American Encyclopedia beginning in 1980, Encyclopedia.com since 1998, Encarta from 2000 to 2009, Wikipedia since 2001, and Encyclopædia Britannica since 2016.

March 9 is the 68th day of the year in the Gregorian calendar; 297 days remain until the end of the year.