What is Linux? How does it work?
What is Open Source? ... and what it isn't!
Documentaries
Most of you might have watched the "Steve Jobs" and/or "Pirates of Silicon Valley" movies. There are some other related documentary movies, too. This documentary talks about the open source movement - which also took place towards the end of the previous millennium, starting 1980s with GNU project.
Open source in real world ...
Software for Graphic Design and Image processing