Free Software Movement was started by Richard M Stallman founder of GNU Project. GNU is recursive acronym of GNU is Not Unix.
Free software is a matter of liberty, not price. To understand the concept, you should think of free as in free speech, not as in free beer. Free as in Freedom. This statement is very confusing because when talking about free software, it is best to avoid using terms like give away or for free, because those terms imply that the issue is about price, not freedom.
Free software is a matter of the users' freedom to run, copy, distribute, study, change and improve the software. It's diferent from open source.
References :
1. http://www.gnu.org/philosophy/free-sw.html
2. http://www.gnu.org/philosophy/open-source-misses-the-point.html
3. http://opensource.org/docs/osd
4. http://en.wikipedia.org/wiki/Free_software_movement
