web-based encyclopedia

Though launched as a website back in March of that year and defunct since September 2003, the pioneering venture from Jimmy Wales and Larry Sanger published its first reference article on this day in 2000—on atonal music.
Compiled by volunteers like its successor Wikipedia, Nupedia was intended as free content but plans were in place to run advertisements and generate revenue on the platform. It was not until November 2000 that the second full length article (on the Western canon of classical music) was ready but not for lack of submissions and rather an overly lengthy peer-review and vetting process.