The sixth most widely used website in the world is not run anything like the others in the top 10. It is not operated by a sophisticated corporation but by a leaderless collection of volunteers who generally work under pseudonyms and habitually bicker with each other.The volunteer workforce that built the project's flagship, the English-language Wikipedia-and must defend it against vandalism, hoaxes, and manipulation-has shrunk by more than a third since 2007 and is still shrinking.