When we call software “free”, we mean that it respects the essential freedoms of its users: the freedom to execute it, to study and edit it, and to distribute it with or without modification. This is a matter of freedom, not price, so imagine “free speech” rather than “free beer”.
These freedoms are vital. They are essential not only for individual users, but for society as a whole, because they promote social solidarity – that is, sharing and cooperation. They become even more important as our culture and livelihoods become increasingly dependent on digital technology. In a world of digital sounds, images and words, free software is becoming increasingly essential to freedom in general.
Almost all open source software is free software. Both terms describe the same category of software, but they signify views based on fundamentally different values. Open source is a development method; free software is a social movement. For the free software movement, free software is an ethical imperative because only free software respects the freedom of users. In contrast, open source philosophy looks at issues in terms of how to make software “better” – only in a practical sense. It says that proprietary software is the worst solution to the practical problem presented. However, for the free software movement, proprietary software is a social problem, and the solution is to stop using it and switch to free software.
The term “free software” is subject to misinterpretation: the unintended meaning of “software you can get at zero cost” fits the term just as well as – “software that gives the user certain freedoms”. We solve this problem by publishing a definition of free software and saying, “Think ‘free speech’ not ‘free beer’.” This is not a perfect solution; it cannot completely eliminate the problem. An unambiguous and correct term would be better if it did not encapsulate other problems….
The official definition of “open source software” (which is published by the Open Source Action Team and is too long to cite here) was derived (indirectly) from our free software criteria. It’s not the same thing, it’s a bit broader in some aspects, so open source proponents have adopted several licenses that we find unacceptably rigid. In addition, they judge solely on the source code license, whereas our criterion also depends on whether the device will allow a modified version of the software to run. Nevertheless, their definition is consistent with ours in most cases.
However, the obvious meaning of “open source software” is “you can look at the source code”, and most people seem to think that is what it means. This criterion is much weaker than the definition of free software, and also much weaker than the official definition of open source. It is met by a lot of software that is neither free nor open source.
Open source advocates try to correct this by pointing to their official definition, but this correction is less effective for them than it is for us. The term “free software” has two natural meanings, one of which we mean, so that a person who has grasped the idea of “free speech, not free beer” will never misunderstand it again. But the term “open source” has only one natural meaning, and it’s different from the meaning its proponents would like to put into it. So there is no intelligible way to explain and justify its official definition. This leads to even more confusion.
The notion of “open source” has since been transferred to other activities, such as government, education, and research, where there is no such thing as “source” and where software licensing criteria simply do not apply. The only thing these activities have in common is that they invite people to participate. They have stretched the notion so broadly that it only means participation from the outside.
