From the movie "Revolution OS" [1], Richard Stallman explaining Copyleft:<p><i>"If we put the software in the public domain, somebody else would be able to make a little bit of changes and turn that into a proprietary software package, which means that
the users would be running our software, but they wouldn't have freedom to cooperate and share."</i><p><i>"And what we do is, we say, this software is copyrighted and we, the authors give you permission to redistribute copies, we give you permission to change, we give you permission to add to it. But when you redistribute it, it has to be under these terms, no more and no less. So that whoever gets it from you also gets the freedom to cooperate with other people, if he wants to. And then, in this way everywhere the software goes, the freedom goes, too. And it becomes an inalienable right to cooperate with other people and form a community."</i><p>Bruce Perens, on the choice of the GPL for Debian:<p><i>"Uh, it's one of the few software licenses that was written from the standpoint of the community rather than from the standpoint of um, protecting a company or um, as is the case with MIT and BSD license, performing the goals of a government grant program. Uh, and the GPL is really unique in that. It's not just a license. It's a whole philosophy that, I think, motivated the open source definition."</i><p>MongoDB tried to protect its company's profits, and as a result, Amazon [and its users] now have a proprietary product rather than an open source one. Could have gotten free fixes from the biggest lab in the world, but instead they're getting jack squat. And since Amazon's product is proprietary, now users and the community have less freedom.<p>Linus is asked at the end if he's bothered that he's not cashing out on billions of dollars of use, and he basically doesn't care. He just wanted people to work on the software. If Linux had the same licensing scheme, it may have remained a hobby operating system.<p>[1] <a href="https://www.youtube.com/watch?v=Eluzi70O-P4#t=17m" rel="nofollow">https://www.youtube.com/watch?v=Eluzi70O-P4#t=17m</a>