A program is free software if the program’s users have the four essential freedoms:
- The freedom to run the program as you wish, for any purpose (freedom 0).
- The freedom to study how the program works, and change it so it does your computing as you wish (freedom 1). Access to the source code is a precondition for this.
- The freedom to redistribute copies so you can help your neighbor (freedom 2).
- The freedom to distribute copies of your modified versions to others (freedom 3). By doing this you can give the whole community a chance to benefit from your changes. Access to the source code is a precondition for this.
Software manuals must be free, for the same reasons that software must be free, and because the manuals are in effect part of the software.
The same arguments also make sense for other kinds of works of practical use — that is to say, works that embody useful knowledge, such as educational works and reference works. Wikipedia is the best-known example.
Any kind of work can be free, and the definition of free software has been extended to a definition of free cultural works applicable to any kind of works.
Another group has started using the term “open source” to mean something close (but not identical) to “free software”. We prefer the term “free software” because, once you have heard that it refers to freedom rather than price, it calls to mind freedom. The word “open” never refers to freedom.
The software freedom day is being celebrated tomorrow.. do try to show up! 🙂 It would certainly be nice to see you around. More information can be found on Chetansheel Yuwa’s blog post @ here. We hoep to see you!