viewpoints VDOI:10.1145/1516046.1516058 Richard Stallman Viewpoint Why “Open Source” Misses the Point of Free Software Decoding the important differences in terminology, underlying philosophy, and value systems between two similar categories of software. HEN WE CALL software appeal to business executives by citing “free,” we mean it re- practical benefits, while avoiding ideas spects the users’ essen- of right and wrong they might not like tial freedoms: the free- to hear. Other proponents flatly reject- dom to run it, to study ed the free software movement’s ethi- Wand change it, and to redistribute cal and social values. Whichever their copies with or without changes (see views, when campaigning for “open http://www.gnu.org/philosophy/free- source” they did not cite or advocate sw.html). This is a matter of freedom, those values. The term “open source” not price, so think of “free speech,” not quickly became associated with the “free beer.” practice of citing only practical values, These freedoms are vitally impor- such as making powerful, reliable soft- tant. They are essential, not just for the ware. Most of the supporters of “open individual users’ sake, but because they source” have come to it since then, promote social solidarity—that is, shar- the development of the free operating and that practice is what they take it to ing and cooperation. They become even system GNU, so we could avoid the non- mean. more important as more aspects of our free operating systems that deny free- Nearly all open source software is culture and life activities are digitized. dom to their users. During the 1980s, free software; the two terms describe In a world of digital sounds, images, we developed most of the essential almost the same category of software. and words, free software increasingly components of such a system, as well But they stand for views based on fun- equates with freedom in general. as the GNU General Public License (see damentally different values. Open Tens of millions of people around http://www.gnu.org/licenses/gpl.html), source is a development methodology; the world now use free software; the a license designed specifically to pro- free software is a social movement. For schools in regions of India and Spain tect freedom for all users of a program. the free software movement, free soft- now teach all students to use the free However, not all of the users and de- ware is an ethical imperative, because GNU/Linux operating system (see velopers of free software agreed with the only free software respects the users’ http://www.gnu.org/gnu/linux-and- goals of the free software movement. In freedom. By contrast, the philosophy of gnu.html). But most of these users have 1998, a part of the free software com- open source considers issues in terms never heard of the ethical reasons for munity splintered off and began cam- of how to make software “better”—in which we developed this system and paigning in the name of “open source.” a practical sense only. It says that non- built the free software community, be- The term was originally proposed to free software is a suboptimal solution. cause today this system and commu- avoid a possible misunderstanding For the free software movement, how- nity are more often described as “open of the term “free software,” but it soon ever, non-free software is a social prob- source,” and attributed to a different became associated with philosophical lem, and moving to free software is the philosophy in which these freedoms views quite different from those of the solution. are hardly mentioned. free software movement. Free software. Open source. If it’s The free software movement has Some of the proponents of “open the same software, does it matter campaigned for computer users’ free- source” considered it a marketing cam- which name you use? Yes, because dif- dom since 1983. In 1984 we launched paign for free software, which would ferent words convey different ideas. JUNE 2009 | VOL. 52 | NO. 6 | COMMUNICATIONS OF THE ACM 31 viewpoints While a free program by any other the same; it is a little looser in some re- considered free software licenses. name would give you the same free- spects, so open source supporters have dom today, establishing freedom in accepted a few licenses that we consid- Different Values Can Lead a lasting way depends above all on er unacceptably restrictive of the users. to Similar Conclusions… teaching people to value freedom. If Nonetheless, it is fairly close to our defi- But Not Always you want to help do this, it is essential nition in practice. Radical groups in the 1960s had a repu- to speak about “free software.” However, the obvious meaning for tation for factionalism: some organiza- We in the free software movement the expression “open source software” tions split because of disagreements don’t think of the open source camp is “You can look at the source code,” on details of strategy, and the two re- as an enemy; the enemy is proprietary and most people seem to think that’s sultant groups treated each other as (non-free) software. But we want people what it means. That is a much weaker enemies despite having similar basic to know we stand for freedom, so we do criterion than free software, and much goals and values. The right wing made not accept being misidentified as open weaker than the official definition of much of this, and used it to criticize the source supporters. open source. It includes many pro- entire left. grams that are neither free nor open Some try to disparage the free soft- Common Misunderstandings of source. Since that obvious meaning ware movement by comparing our “Free Software” and “Open Source” for “open source” is not the meaning disagreement with open source to the The term “free software” has a problem that its advocates intend, the result disagreements of those radical groups. of misinterpretation: an unintended is that most people misunderstand They have it backward. We disagree meaning, “software you can get for zero the term. Here is how writer Neal Ste- with the open source camp on the ba- price,” fits the term just as well as the phenson defined “open source”: Li- sic goals and values, but their views and intended meaning, “software that gives nux is “open source” software meaning, ours lead in many cases to the same the user certain freedoms.” We address simply, that anyone can get copies of its practical behavior—such as developing this problem by publishing the defi- source code files. free software. nition of free software, and by saying I don’t think Stephenson deliberately As a result, people from the free “Think of free speech, not free beer.” sought to reject or dispute the “official” software movement and the open This is not a perfect solution; it cannot definition. I think he simply applied the source camp often work together on completely eliminate the problem. An conventions of the English language to practical projects such as software de- unambiguous, correct term would be come up with a meaning for the term. velopment. It is remarkable that such better, if it didn’t have other problems. The state of Kansas published a similar different philosophical views can so Unfortunately, all the alternatives definition: Make use of open-source soft- often motivate different people to par- in English have problems of their own. ware (OSS). OSS is software for which the ticipate in the same projects. Nonethe- We’ve looked at many alternatives that source code is freely and publicly avail- less, these views are very different, and people have suggested, but none is able, though the specific licensing agree- there are situations where they lead to so clearly correct that switching to it ments vary as to what one is allowed to do very different actions. would be a good idea. Every proposed with that code. The idea of open source is that allow- replacement for “free software” has Open source supporters try to deal ing users to change and redistribute the some kind of semantic problem—and with this by pointing to their official software will make it more powerful and this includes “open source software.” definition, but that corrective approach reliable. But this is not guaranteed. De- The official definition of “open is less effective for them than it is for us. velopers of proprietary software are not source software,” which is published by The term “free software” has two natu- necessarily incompetent. Sometimes the Open Source Initiative (see http:// ral meanings, one of which is the in- they produce a program that is power- opensource.org/docs/osd) and too long tended meaning, so a person who has ful and reliable, even though it does not to cite here, was derived indirectly from grasped the idea of “free speech, not respect the users’ freedom. How will our criteria for free software. It is not free beer” will not get it wrong again. free software activists and open source But “open source” has only one natural enthusiasts react to that? meaning, which is different from the A pure open source enthusiast, one meaning its supporters intend. So there that is not at all influenced by the ide- Open source is is no succinct way to explain and justify als of free software, will say, “I am sur- a development the official definition of “open source.” prised you were able to make the pro- That makes for worse confusion. gram work so well without using our methodology; free Another common misunderstand- development model, but you did.