What Are The Four Essential Freedoms Of Free Software?
"Freedom Zero is the freedom to run the program as you wish, and that includes using it commercially. Freedom One is the freedom to study the source code and change it so that the program does your computing the way you wish. These two freedoms give users individual control of the program. However individual control is not enough. You need collective control as well so that any group of people can work together to exercise control over the program. And that requires two more essential freedoms. Freedom Two is the freedom to make exact copies and distribute them, as you wish, and Freedom Three is the freedom to make copies of your modified version, and distribute them to others, if you wish. In every non-free program is an instrument of unjust power. Our goal is to put an end to that."