"Open source is a development methodology; free software is a social movement. For the free software movement, free software is an ethical imperative, because only free software respects the users' freedom. By contrast, the philosophy of open source considers issues in terms of how to make software “better”—in a practical sense only. It says that non-free software is a suboptimal solution.

“Open Source” advocate: «...I associate much more with the "Open Source" (also as Richard defines it) camp, and am open to the existence and use of proprietary software...» --

Free software is software you can study, modify and share without restriction. But unlike proprietary software, there is no big budget marketing campaign behind it. Rather, people discover it and come to value the freedom it provides. What are these people's motivations for working on free software? Why is community and sharing so important? Why should everyone be using free software?

«...On this subject, I had an interesting email conversation with Richard Stallman, founder of the Free Software Foundation, who differentiated for me the difference between "open source" and "free software," ...» -- Free Software, Free Society: Why Barack Obama should support the Free Software Movement

"..RMS’s other mission here is to promote the Free Software Movement. The creator of the GPL...is at pains to correct misunderstandings of what the term free software means and to draw a distinction between it and the open source movement.

"Not only is the free software movement a source of software and licenses, it is also a source of inspiration. In particular, free software has been cited by many in the nascent free culture movement as an explicit source of inspiration and point of departure.

It seems we mostly hear the term "Open Source" bandied about in the press. Save for the occasional references to the Free Software Foundation and FSF Europe, one might get the impression that the Free Software movement is floundering along, all but forgotten in the annals of history. In reality, though, the Free Software movement is very much alive and kicking.

"Free software is a good thing, its empowering, I might even go as far as to say its the way things should be done. One of the biggest threats to free software at the moment is “web services”, or if you’re an airy fairy Web 2.0 person “The Cloud” (airy could, geddit?).

"...The first step towards acknowledging the Free Software Movement is to understand that `Free Software’ and `Open Source Software’ are two different entities. And that we, in the media, have been quite unjust to the movement by using the terms `Free Software’ and `Open Source’ interchangeably..."