There are lots of resources available online to learn about Free and Open Source Software.
If you want to understand the essence and ideals of this movement, a great start would be to read the following 4 books. After reading these, you will have a good grasp of the history and philosophy of freedom in the technology world.
Copyright © 2006-2008 Corey Goldberg
Disclaimer The opinions expressed herein are my own personal opinions and do not represent my employer's view in any way.