Free Software is software that you are free to share with your family, friends, and neighbors.
Isn’t that a nice thing? It doesn’t cost anything to make copies of digital information, and we have these wonderful machines and a worldwide network that are perfect for copying and sharing. Why not use these tools to freely share our accumulated knowledge? You may also modify the software, if you are so inclined, and are free to distribute your modified version. You don’t have to ask for permission for any of this, either.
That puts things rather simply, and leaves out some fine print, but this is essentially how it works. And it does work. We’re in the midst of a free software revolution! Although like all revolutions, there are counterforces at work.
For a good introduction to what free software is all about, I recommend the GNU philosophy essays. For starters: “Why Software Should Not Have Owners” and “The Free Software Definition” by Richard Stallman.
Counterforces include harmful software patents, Digital Restrictions Management (DRM), and the Digital Millennium Copyright Act (DMCA). These are all tools used in different ways to prevent people from using free software to achieve the goals of sharing and cooperation and just getting things done.