Free software is a matter of liberty, not price
The Free Software Foundation is working to secure freedom for computer users by promoting the development and use of free (as in freedom) software and documentation — particularly the GNU/Linux operating system — and by campaigning against threats to computer user freedom like Digital Restrictions Management (DRM).
The free software movement is one the most successful social movements to emerge in the past 25 years, driven by a worldwide community of ethical programmers dedicated to freedom. Its impact on our future is growing every day. But the ultimate success of the free software movement depends on teaching our friends and neighbours to recognize the danger of not having software freedom -- freedom that they have lost, without recognizing it, to proprietary software.
— Peter Brown, Executive Director, Free Software Foundation