Wikipedia – written and edited entirely by un-paid users – is the fifth most popular website in the world.

What's up with that?

How can a company that spends NOTHING creating content have blown past all but four sites on the planet?

In this exclusive Business Insider interview, Wikipedia founder Jimmy Wales explains.

Here are three fun details from the interview:

In an earlier version of Wikipedia, users had to fax their diplomas to prove that they were qualified to write entries (that one went nowhere fast)

Wikipedia doesn't have a single paid employee responsible for content (writing, editing or any of the sort.). Wikipedia is more than 10X as big as the New York Times, which has 1,200 of them.

In the German version of Wikipedia, editors give each other 'gummy bears' for good spelling.

This interview is part of our Leadership series, presented with limited commercial interruption.

Production by Bright Red Pixels.