What is Free Software?

A lot of people confuse Free Software with for no charge software. That is a grave problem in English. The word Free can convey two meanings not directly related. Free (as in for no charge) and Free (as in Freedom). A software that you get for no charge isn't necessarily free, as in wont provide you with the essential freedoms and wont necessarily respect your freedom.

Free Software can be free and can be for a certain royalty, nothing wrong with either of them. 

What Free Software is about are the 4 essential freedoms:

Freedom 0: The freedom to run the program, for any purpose.

Freedom 1: The freedom to study how the program works, and adapt it to your needs. Access to the source code is a precondition for this.

Freedom 2: The freedom to redistribute copies so you can help your neighbor.

Freedom 3: The freedom to improve the program, and release your improvements to the public, so that the whole community benefits. Access to the source code is a precondition for this.

The Free Software Definition