5 originally published in the book "Open Sources"
7 The first software-sharing community
9 When I started working at the MIT Artificial Intelligence Lab in 1971,
10 I became part of a software-sharing community that had existed for
11 many years. Sharing of software was not limited to our particular
12 community; it is as old as computers, just as sharing of recipes is as
13 old as cooking. But we did it more than most.
15 The AI Lab used a timesharing operating system called ITS (the
16 Incompatible Timesharing System) that the lab's staff hackers (1) had
17 designed and written in assembler language for the Digital PDP-10, one
18 of the large computers of the era. As a member of this community, an
19 AI lab staff system hacker, my job was to improve this system.
21 We did not call our software "free software", because that term did
22 not yet exist; but that is what it was. Whenever people from another
23 university or a company wanted to port and use a program, we gladly
24 let them. If you saw someone using an unfamiliar and interesting
25 program, you could always ask to see the source code, so that you
26 could read it, change it, or cannibalize parts of it to make a new
29 (1) The use of "hacker" to mean "security breaker" is a confusion on
30 the part of the mass media. We hackers refuse to recognize that
31 meaning, and continue using the word to mean, "Someone who loves to
32 program and enjoys being clever about it."
34 The collapse of the community
36 The situation changed drastically in the early 1980s when Digital
37 discontinued the PDP-10 series. Its architecture, elegant and powerful
38 in the 60s, could not extend naturally to the larger address spaces
39 that were becoming feasible in the 80s. This meant that nearly all of
40 the programs composing ITS were obsolete.
42 The AI lab hacker community had already collapsed, not long before. In
43 1981, the spin-off company Symbolics had hired away nearly all of the
44 hackers from the AI lab, and the depopulated community was unable to
45 maintain itself. (The book Hackers, by Steve Levy, describes these
46 events, as well as giving a clear picture of this community in its
47 prime.) When the AI lab bought a new PDP-10 in 1982, its
48 administrators decided to use Digital's non-free timesharing system
51 The modern computers of the era, such as the VAX or the 68020, had
52 their own operating systems, but none of them were free software: you
53 had to sign a nondisclosure agreement even to get an executable copy.
55 This meant that the first step in using a computer was to promise not
56 to help your neighbor. A cooperating community was forbidden. The rule
57 made by the owners of proprietary software was, "If you share with
58 your neighbor, you are a pirate. If you want any changes, beg us to
61 The idea that the proprietary software social system--the system that
62 says you are not allowed to share or change software--is antisocial,
63 that it is unethical, that it is simply wrong, may come as a surprise
64 to some readers. But what else could we say about a system based on
65 dividing the public and keeping users helpless? Readers who find the
66 idea surprising may have taken proprietary social system as given, or
67 judged it on the terms suggested by proprietary software businesses.
68 Software publishers have worked long and hard to convince people that
69 there is only one way to look at the issue.
71 When software publishers talk about "enforcing" their "rights" or
72 "stopping piracy", what they actually *say* is secondary. The real
73 message of these statements is in the unstated assumptions they take
74 for granted; the public is supposed to accept them uncritically. So
77 One assumption is that software companies have an unquestionable
78 natural right to own software and thus have power over all its users.
79 (If this were a natural right, then no matter how much harm it does to
80 the public, we could not object.) Interestingly, the US Constitution
81 and legal tradition reject this view; copyright is not a natural
82 right, but an artificial government-imposed monopoly that limits the
83 users' natural right to copy.
85 Another unstated assumption is that the only important thing about
86 software is what jobs it allows you to do--that we computer users
87 should not care what kind of society we are allowed to have.
89 A third assumption is that we would have no usable software (or, would
90 never have a program to do this or that particular job) if we did not
91 offer a company power over the users of the program. This assumption
92 may have seemed plausible, before the free software movement
93 demonstrated that we can make plenty of useful software without
96 If we decline to accept these assumptions, and judge these issues
97 based on ordinary common-sense morality while placing the users first,
98 we arrive at very different conclusions. Computer users should be free
99 to modify programs to fit their needs, and free to share software,
100 because helping other people is the basis of society.
102 There is no room here for an extensive statement of the reasoning
103 behind this conclusion, so I refer the reader to the web page,
104 <http://www.gnu.org/philosophy/why-free.html>.
106 A stark moral choice.
108 With my community gone, to continue as before was impossible. Instead,
109 I faced a stark moral choice.
111 The easy choice was to join the proprietary software world, signing
112 nondisclosure agreements and promising not to help my fellow hacker.
113 Most likely I would also be developing software that was released
114 under nondisclosure agreements, thus adding to the pressure on other
115 people to betray their fellows too.
117 I could have made money this way, and perhaps amused myself writing
118 code. But I knew that at the end of my career, I would look back on
119 years of building walls to divide people, and feel I had spent my life
120 making the world a worse place.
122 I had already experienced being on the receiving end of a
123 nondisclosure agreement, when someone refused to give me and the MIT
124 AI lab the source code for the control program for our printer. (The
125 lack of certain features in this program made use of the printer
126 extremely frustrating.) So I could not tell myself that nondisclosure
127 agreements were innocent. I was very angry when he refused to share
128 with us; I could not turn around and do the same thing to everyone
131 Another choice, straightforward but unpleasant, was to leave the
132 computer field. That way my skills would not be misused, but they
133 would still be wasted. I would not be culpable for dividing and
134 restricting computer users, but it would happen nonetheless.
136 So I looked for a way that a programmer could do something for the
137 good. I asked myself, was there a program or programs that I could
138 write, so as to make a community possible once again?
140 The answer was clear: what was needed first was an operating system.
141 That is the crucial software for starting to use a computer. With an
142 operating system, you can do many things; without one, you cannot run
143 the computer at all. With a free operating system, we could again have
144 a community of cooperating hackers--and invite anyone to join. And
145 anyone would be able to use a computer without starting out by
146 conspiring to deprive his or her friends.
148 As an operating system developer, I had the right skills for this job.
149 So even though I could not take success for granted, I realized that I
150 was elected to do the job. I chose to make the system compatible with
151 Unix so that it would be portable, and so that Unix users could easily
152 switch to it. The name GNU was chosen following a hacker tradition, as
153 a recursive acronym for "GNU's Not Unix."
155 An operating system does not mean just a kernel, barely enough to run
156 other programs. In the 1970s, every operating system worthy of the
157 name included command processors, assemblers, compilers, interpreters,
158 debuggers, text editors, mailers, and much more. ITS had them, Multics
159 had them, VMS had them, and Unix had them. The GNU operating system
160 would include them too.
162 Later I heard these words, attributed to Hillel (1):
164 If I am not for myself, who will be for me?
165 If I am only for myself, what am I?
168 The decision to start the GNU project was based on a similar spirit.
170 (1) As an Atheist, I don't follow any religious leaders, but I
171 sometimes find I admire something one of them has said.
175 The term "free software" is sometimes misunderstood--it has nothing to
176 do with price. It is about freedom. Here, therefore, is the definition
177 of free software: a program is free software, for you, a particular
180 * You have the freedom to run the program, for any purpose.
181 * You have the freedom to modify the program to suit your needs. (To
182 make this freedom effective in practice, you must have access to
183 the source code, since making changes in a program without having
184 the source code is exceedingly difficult.)
185 * You have the freedom to redistribute copies, either gratis or for
187 * You have the freedom to distribute modified versions of the
188 program, so that the community can benefit from your improvements.
190 Since "free" refers to freedom, not to price, there is no
191 contradiction between selling copies and free software. In fact, the
192 freedom to sell copies is crucial: collections of free software sold
193 on CD-ROMs are important for the community, and selling them is an
194 important way to raise funds for free software development. Therefore,
195 a program which people are not free to include on these collections is
198 Because of the ambiguity of "free", people have long looked for
199 alternatives, but no one has found a suitable alternative. The English
200 Language has more words and nuances than any other, but it lacks a
201 simple, unambiguous, word that means "free," as in
202 freedom--"unfettered," being the word that comes closest in meaning.
203 Such alternatives as "liberated", "freedom" and "open" have either the
204 wrong meaning or some other disadvantage.
206 GNU software and the GNU system
208 Developing a whole system is a very large project. To bring it into
209 reach, I decided to adapt and use existing pieces of free software
210 wherever that was possible. For example, I decided at the very
211 beginning to use TeX as the principal text formatter; a few years
212 later, I decided to use the X Window System rather than writing
213 another window system for GNU.
215 Because of this decision, the GNU system is not the same as the
216 collection of all GNU software. The GNU system includes programs that
217 are not GNU software, programs that were developed by other people and
218 projects for their own purposes, but which we can use because they are
221 Commencing the project
223 In January 1984 I quit my job at MIT and began writing GNU software.
224 Leaving MIT was necessary so that MIT would not be able to interfere
225 with distributing GNU as free software. If I had remained on the
226 staff, MIT could have claimed to own the work, and could have imposed
227 their own distribution terms, or even turned the work into a
228 proprietary software package. I had no intention of doing a large
229 amount of work only to see it become useless for its intended purpose:
230 creating a new software-sharing community.
232 However, Professor Winston, then the head of the MIT AI Lab, kindly
233 invited me to keep using the lab's facilities.
237 Shortly before beginning the GNU project, I heard about the Free
238 University Compiler Kit, also known as VUCK. (The Dutch word for
239 "free" is written with a V.) This was a compiler designed to handle
240 multiple languages, including C and Pascal, and to support multiple
241 target machines. I wrote to its author asking if GNU could use it.
243 He responded derisively, stating that the university was free but the
244 compiler was not. I therefore decided that my first program for the
245 GNU project would be a multi-language, multi-platform compiler.
247 Hoping to avoid the need to write the whole compiler myself, I
248 obtained the source code for the Pastel compiler, which was a
249 multi-platform compiler developed at Lawrence Livermore Lab. It
250 supported, and was written in, an extended version of Pascal, designed
251 to be a system-programming language. I added a C front end, and began
252 porting it to the Motorola 68000 computer. But I had to give that up
253 when I discovered that the compiler needed many megabytes of stack
254 space, and the available 68000 Unix system would only allow 64k.
256 I then realized that the Pastel compiler functioned by parsing the
257 entire input file into a syntax tree, converting the whole syntax tree
258 into a chain of "instructions", and then generating the whole output
259 file, without ever freeing any storage. At this point, I concluded I
260 would have to write a new compiler from scratch. That new compiler is
261 now known as GCC; none of the Pastel compiler is used in it, but I
262 managed to adapt and use the C front end that I had written. But that
263 was some years later; first, I worked on GNU Emacs.
267 I began work on GNU Emacs in September 1984, and in early 1985 it was
268 beginning to be usable. This enabled me to begin using Unix systems to
269 do editing; having no interest in learning to use vi or ed, I had done
270 my editing on other kinds of machines until then.
272 At this point, people began wanting to use GNU Emacs, which raised the
273 question of how to distribute it. Of course, I put it on the anonymous
274 ftp server on the MIT computer that I used. (This computer,
275 prep.ai.mit.edu, thus became the principal GNU ftp distribution site;
276 when it was decommissioned a few years later, we transferred the name
277 to our new ftp server.) But at that time, many of the interested
278 people were not on the Internet and could not get a copy by ftp. So
279 the question was, what would I say to them?
281 I could have said, "Find a friend who is on the net and who will make
282 a copy for you." Or I could have done what I did with the original
283 PDP-10 Emacs: tell them, "Mail me a tape and a SASE, and I will mail
284 it back with Emacs on it." But I had no job, and I was looking for
285 ways to make money from free software. So I announced that I would
286 mail a tape to whoever wanted one, for a fee of $150. In this way, I
287 started a free software distribution business, the precursor of the
288 companies that today distribute entire Linux-based GNU systems.
290 Is a program free for every user?
292 If a program is free software when it leaves the hands of its author,
293 this does not necessarily mean it will be free software for everyone
294 who has a copy of it. For example, public domain software (software
295 that is not copyrighted) is free software; but anyone can make a
296 proprietary modified version of it. Likewise, many free programs are
297 copyrighted but distributed under simple permissive licenses which
298 allow proprietary modified versions.
300 The paradigmatic example of this problem is the X Window System.
301 Developed at MIT, and released as free software with a permissive
302 license, it was soon adopted by various computer companies. They added
303 X to their proprietary Unix systems, in binary form only, and covered
304 by the same nondisclosure agreement. These copies of X were no more
305 free software than Unix was.
307 The developers of the X Window System did not consider this a
308 problem--they expected and intended this to happen. Their goal was not
309 freedom, just "success", defined as "having many users." They did not
310 care whether these users had freedom, only that they should be
313 This lead to a paradoxical situation where two different ways of
314 counting the amount of freedom gave different answers to the question,
315 "Is this program free?" If you judged based on the freedom provided by
316 the distribution terms of the MIT release, you would say that X was
317 free software. But if you measured the freedom of the average user of
318 X, you would have to say it was proprietary software. Most X users
319 were running the proprietary versions that came with Unix systems, not
322 Copyleft and the GNU GPL
324 The goal of GNU was to give users freedom, not just to be popular. So
325 we needed to use distribution terms that would prevent GNU software
326 from being turned into proprietary software. The method we use is
327 called "copyleft".(1)
329 Copyleft uses copyright law, but flips it over to serve the opposite
330 of its usual purpose: instead of a means of privatizing software, it
331 becomes a means of keeping software free.
333 The central idea of copyleft is that we give everyone permission to
334 run the program, copy the program, modify the program, and distribute
335 modified versions--but not permission to add restrictions of their
336 own. Thus, the crucial freedoms that define "free software" are
337 guaranteed to everyone who has a copy; they become inalienable rights.
339 For an effective copyleft, modified versions must also be free. This
340 ensures that work based on ours becomes available to our community if
341 it is published. When programmers who have jobs as programmers
342 volunteer to improve GNU software, it is copyleft that prevents their
343 employers from saying, "You can't share those changes, because we are
344 going to use them to make our proprietary version of the program."
346 The requirement that changes must be free is essential if we want to
347 ensure freedom for every user of the program. The companies that
348 privatized the X Window System usually made some changes to port it to
349 their systems and hardware. These changes were small compared with the
350 great extent of X, but they were not trivial. If making changes were
351 an excuse to deny the users freedom, it would be easy for anyone to
352 take advantage of the excuse.
354 A related issue concerns combining a free program with non-free code.
355 Such a combination would inevitably be non-free; whichever freedoms
356 are lacking for the non-free part would be lacking for the whole as
357 well. To permit such combinations would open a hole big enough to sink
358 a ship. Therefore, a crucial requirement for copyleft is to plug this
359 hole: anything added to or combined with a copylefted program must be
360 such that the larger combined version is also free and copylefted.
362 The specific implementation of copyleft that we use for most GNU
363 software is the GNU General Public License, or GNU GPL for short. We
364 have other kinds of copyleft that are used in specific circumstances.
365 GNU manuals are copylefted also, but use a much simpler kind of
366 copyleft, because the complexity of the GNU GPL is not necessary for
369 (1) In 1984 or 1985, Don Hopkins (a very imaginative fellow) mailed me
370 a letter. On the envelope he had written several amusing sayings,
371 including this one: "Copyleft--all rights reversed." I used the word
372 "copyleft" to name the distribution concept I was developing at the
375 The Free Software Foundation
377 As interest in using Emacs was growing, other people became involved
378 in the GNU project, and we decided that it was time to seek funding
379 once again. So in 1985 we created the Free Software Foundation, a
380 tax-exempt charity for free software development. The FSF also took
381 over the Emacs tape distribution business; later it extended this by
382 adding other free software (both GNU and non-GNU) to the tape, and by
383 selling free manuals as well.
385 The FSF accepts donations, but most of its income has always come from
386 sales--of copies of free software, and of other related services.
387 Today it sells CD-ROMs of source code, CD-ROMs with binaries, nicely
388 printed manuals (all with freedom to redistribute and modify), and
389 Deluxe Distributions (where we build the whole collection of software
390 for your choice of platform).
392 Free Software Foundation employees have written and maintained a
393 number of GNU software packages. Two notable ones are the C library
394 and the shell. The GNU C library is what every program running on a
395 GNU/Linux system uses to communicate with Linux. It was developed by a
396 member of the Free Software Foundation staff, Roland McGrath. The
397 shell used on most GNU/Linux systems is BASH, the Bourne Again
398 Shell(1), which was developed by FSF employee Brian Fox.
400 We funded development of these programs because the GNU project was
401 not just about tools or a development environment. Our goal was a
402 complete operating system, and these programs were needed for that
405 (1) "Bourne again Shell" is a joke on the name ``Bourne Shell'', which
406 was the usual shell on Unix.
408 Free software support
410 The free software philosophy rejects a specific widespread business
411 practice, but it is not against business. When businesses respect the
412 users' freedom, we wish them success.
414 Selling copies of Emacs demonstrates one kind of free software
415 business. When the FSF took over that business, I needed another way
416 to make a living. I found it in selling services relating to the free
417 software I had developed. This included teaching, for subjects such as
418 how to program GNU Emacs and how to customize GCC, and software
419 development, mostly porting GCC to new platforms.
421 Today each of these kinds of free software business is practiced by a
422 number of corporations. Some distribute free software collections on
423 CD-ROM; others sell support at levels ranging from answering user
424 questions, to fixing bugs, to adding major new features. We are even
425 beginning to see free software companies based on launching new free
428 Watch out, though--a number of companies that associate themselves
429 with the term "open source" actually base their business on non-free
430 software that works with free software. These are not free software
431 companies, they are proprietary software companies whose products
432 tempt users away from freedom. They call these "value added", which
433 reflects the values they would like us to adopt: convenience above
434 freedom. If we value freedom more, we should call them "freedom
435 subtracted" products.
439 The principal goal of GNU was to be free software. Even if GNU had no
440 technical advantage over Unix, it would have a social advantage,
441 allowing users to cooperate, and an ethical advantage, respecting the
444 But it was natural to apply the known standards of good practice to
445 the work--for example, dynamically allocating data structures to avoid
446 arbitrary fixed size limits, and handling all the possible 8-bit codes
447 wherever that made sense.
449 In addition, we rejected the Unix focus on small memory size, by
450 deciding not to support 16-bit machines (it was clear that 32-bit
451 machines would be the norm by the time the GNU system was finished),
452 and to make no effort to reduce memory usage unless it exceeded a
453 megabyte. In programs for which handling very large files was not
454 crucial, we encouraged programmers to read an entire input file into
455 core, then scan its contents without having to worry about I/O.
457 These decisions enabled many GNU programs to surpass their Unix
458 counterparts in reliability and speed.
462 As the GNU project's reputation grew, people began offering to donate
463 machines running UNIX to the project. These were very useful, because
464 the easiest way to develop components of GNU was to do it on a UNIX
465 system, and replace the components of that system one by one. But they
466 raised an ethical issue: whether it was right for us to have a copy of
469 UNIX was (and is) proprietary software, and the GNU project's
470 philosophy said that we should not use proprietary software. But,
471 applying the same reasoning that leads to the conclusion that violence
472 in self defense is justified, I concluded that it was legitimate to
473 use a proprietary package when that was crucial for developing free
474 replacement that would help others stop using the proprietary package.
476 But, even if this was a justifiable evil, it was still an evil. Today
477 we no longer have any copies of Unix, because we have replaced them
478 with free operating systems. If we could not replace a machine's
479 operating system with a free one, we replaced the machine instead.
483 As the GNU project proceeded, and increasing numbers of system
484 components were found or developed, eventually it became useful to
485 make a list of the remaining gaps. We used it to recruit developers to
486 write the missing pieces. This list became known as the GNU task list.
487 In addition to missing Unix components, we listed added various other
488 useful software and documentation projects that, we thought, a truly
489 complete system ought to have.
491 Today, hardly any Unix components are left in the GNU task list--those
492 jobs have been done, aside from a few inessential ones. But the list
493 is full of projects that some might call "applications". Any program
494 that appeals to more than a narrow class of users would be a useful
495 thing to add to an operating system.
497 Even games are included in the task list--and have been since the
498 beginning. Unix included games, so naturally GNU should too. But
499 compatibility was not an issue for games, so we did not follow the
500 list of games that Unix had. Instead, we listed a spectrum of
501 different kinds of games that users might like.
505 The GNU C library uses a special kind of copyleft called the GNU
506 Library General Public License, which gives permission to link
507 proprietary software with the library. Why make this exception?
509 It is not a matter of principle; there is no principle that says
510 proprietary software products are entitled to include our code. (Why
511 contribute to a project predicated on refusing to share with us?)
512 Using the LGPL for the C library, or for any library, is a matter of
515 The C library does a generic job; every proprietary system or compiler
516 comes with a C library. Therefore, to make our C library available
517 only to free software would not have given free software any
518 advantage--it would only have discouraged use of our library.
520 One system is an exception to this: on the GNU system (and this
521 includes GNU/Linux), the GNU C library is the only C library. So the
522 distribution terms of the GNU C library determine whether it is
523 possible to compile a proprietary program for the GNU system. There is
524 no ethical reason to allow proprietary applications on the GNU system,
525 but strategically it seems that disallowing them would do more to
526 discourage use of the GNU system than to encourage development of free
529 That is why using the Library GPL is a good strategy for the C
530 library. For other libraries, the strategic decision needs to be
531 considered on a case-by-case basis. When a library does a special job
532 that can help write certain kinds of programs, then releasing it under
533 the GPL, limiting it to free programs only, is a way of helping other
534 free software developers, giving them an advantage against proprietary
537 Consider GNU Readline, a library that was developed to provide
538 command-line editing for BASH. Readline is released under the ordinary
539 GNU GPL, not the Library GPL. This probably does reduce the amount
540 Readline is used, but that is no loss for us. Meanwhile, at least one
541 useful application has been made free software specifically so it
542 could use Readline, and that is a real gain for the community.
544 Proprietary software developers have the advantages money provides;
545 free software developers need to make advantages for each other. I
546 hope some day we will have a large collection of GPL-covered libraries
547 that have no parallel available to proprietary software, providing
548 useful modules to serve as building blocks in new free software, and
549 adding up to a major advantage for further free software development.
553 Eric Raymond says that "Every good work of software starts by
554 scratching a developer's personal itch." Maybe that happens sometimes,
555 but many essential pieces of GNU software were developed in order to
556 have a complete free operating system. They come from a vision and a
557 plan, not from impulse.
559 For example, we developed the GNU C library because a Unix-like system
560 needs a C library, the Bourne-Again Shell (bash) because a Unix-like
561 system needs a shell, and GNU tar because a Unix-like system needs a
562 tar program. The same is true for my own programs--the GNU C compiler,
563 GNU Emacs, GDB and GNU Make.
565 Some GNU programs were developed to cope with specific threats to our
566 freedom. Thus, we developed gzip to replace the Compress program,
567 which had been lost to the community because of the LZW patents. We
568 found people to develop LessTif, and more recently started GNOME and
569 Harmony, to address the problems caused by certain proprietary
570 libraries (see below). We are developing the GNU Privacy Guard to
571 replace popular non-free encryption software, because users should not
572 have to choose between privacy and freedom.
574 Of course, the people writing these programs became interested in the
575 work, and many features were added to them by various people for the
576 sake of their own needs and interests. But that is not why the
579 Unexpected developments
581 At the beginning of the GNU project, I imagined that we would develop
582 the whole GNU system, then release it as a whole. That is not how it
585 Since each component of the GNU system was implemented on a Unix
586 system, each component could run on Unix systems, long before a
587 complete GNU system existed. Some of these programs became popular,
588 and users began extending them and porting them---to the various
589 incompatible versions of Unix, and sometimes to other systems as well.
591 The process made these programs much more powerful, and attracted both
592 funds and contributors to the GNU project. But it probably also
593 delayed completion of a minimal working system by several years, as
594 GNU developers' time was put into maintaining these ports and adding
595 features to the existing components, rather than moving on to write
596 one missing component after another.
600 By 1990, the GNU system was almost complete; the only major missing
601 component was the kernel. We had decided to implement our kernel as a
602 collection of server processes running on top of Mach. Mach is a
603 microkernel developed at Carnegie Mellon University and then at the
604 University of Utah; the GNU HURD is a collection of servers (or ``herd
605 of gnus'') that run on top of Mach, and do the various jobs of the
606 Unix kernel. The start of development was delayed as we waited for
607 Mach to be released as free software, as had been promised.
609 One reason for choosing this design was to avoid what seemed to be the
610 hardest part of the job: debugging a kernel program without a
611 source-level debugger to do it with. This part of the job had been
612 done already, in Mach, and we expected to debug the HURD servers as
613 user programs, with GDB. But it took a long time to make that
614 possible, and the multi-threaded servers that send messages to each
615 other have turned out to be very hard to debug. Making the HURD work
616 solidly has stretched on for many years.
620 The GNU kernel was not originally supposed to be called the HURD. Its
621 original name was Alix--named after the woman who was my sweetheart at
622 the time. She, a Unix system administrator, had pointed out how her
623 name would fit a common naming pattern for Unix system versions; as a
624 joke, she told her friends, "Someone should name a kernel after me." I
625 said nothing, but decided to surprise her with a kernel named Alix.
627 It did not stay that way. Michael Bushnell (now Thomas), the main
628 developer of the kernel, preferred the name HURD, and redefined Alix
629 to refer to a certain part of the kernel--the part that would trap
630 system calls and handle them by sending messages to HURD servers.
632 Ultimately, Alix and I broke up, and she changed her name;
633 independently, the HURD design was changed so that the C library would
634 send messages directly to servers, and this made the Alix component
635 disappear from the design.
637 But before these things happened, a friend of hers came across the
638 name Alix in the HURD source code, and mentioned the name to her. So
639 the name did its job.
643 The GNU Hurd is not ready for production use. Fortunately, another
644 kernel is available. In 1991, Linus Torvalds developed a
645 Unix-compatible kernel and called it Linux. Around 1992, combining
646 Linux with the not-quite-complete GNU system resulted in a complete
647 free operating system. (Combining them was a substantial job in
648 itself, of course.) It is due to Linux that we can actually run a
649 version of the GNU system today.
651 We call this system version GNU/Linux, to express its composition as a
652 combination of the GNU system with Linux as the kernel.
654 Challenges in our future
656 We have proved our ability to develop a broad spectrum of free
657 software. This does not mean we are invincible and unstoppable.
658 Several challenges make the future of free software uncertain; meeting
659 them will require steadfast effort and endurance, sometimes lasting
660 for years. It will require the kind of determination that people
661 display when they value their freedom and will not let anyone take it
664 The following four sections discuss these challenges.
668 Hardware manufacturers increasingly tend to keep hardware
669 specifications secret. This makes it difficult to write free drivers
670 so that Linux and XFree86 can support new hardware. We have complete
671 free systems today, but we will not have them tomorrow if we cannot
672 support tomorrow's computers.
674 There are two ways to cope with this problem. Programmers can do
675 reverse engineering to figure out how to support the hardware. The
676 rest of us can choose the hardware that is supported by free software;
677 as our numbers increase, secrecy of specifications will become a
678 self-defeating policy.
680 Reverse engineering is a big job; will we have programmers with
681 sufficient determination to undertake it? Yes--if we have built up a
682 strong feeling that free software is a matter of principle, and
683 non-free drivers are intolerable. And will large numbers of us spend
684 extra money, or even a little extra time, so we can use free drivers?
685 Yes, if the determination to have freedom is widespread.
689 A non-free library that runs on free operating systems acts as a trap
690 for free software developers. The library's attractive features are
691 the bait; if you use the library, you fall into the trap, because your
692 program cannot usefully be part of a free operating system. (Strictly
693 speaking, we could include your program, but it won't run with the
694 library missing.) Even worse, if a program that uses the proprietary
695 library becomes popular, it can lure other unsuspecting programmers
698 The first instance of this problem was the Motif toolkit, back in the
699 80s. Although there were as yet no free operating systems, it was
700 clear what problem Motif would cause for them later on. The GNU
701 Project responded in two ways: by asking individual free software
702 projects to support the free X toolkit widgets as well as Motif, and
703 by asking for someone to write a free replacement for Motif. The job
704 took many years; LessTif, developed by the Hungry Programmers, became
705 powerful enough to support most Motif applications only in 1997.
707 Between 1996 and 1998, another non-free GUI toolkit library, called
708 Qt, was used in a substantial collection of free software, the desktop
711 Free GNU/Linux systems were unable to use KDE, because we could not
712 use the library. However, some commercial distributors of GNU/Linux
713 systems who were not strict about sticking with free software added
714 KDE to their systems--producing a system with more capabilities, but
715 less freedom. The KDE group was actively encouraging more programmers
716 to use Qt, and millions of new "Linux users" had never been exposed to
717 the idea that there was a problem in this. The situation appeared
720 The free software community responded to the problem in two ways:
723 GNOME, the GNU Network Object Model Environment, is GNU's desktop
724 project. Started in 1997 by Miguel de Icaza, and developed with the
725 support of Red Hat Software, GNOME set out to provide similar desktop
726 facilities, but using free software exclusively. It has technical
727 advantages as well, such as supporting a variety of languages, not
728 just C++. But its main purpose was freedom: not to require the use of
729 any non-free software.
731 Harmony is a compatible replacement library, designed to make it
732 possible to run KDE software without using Qt.
734 In November 1998, the developers of Qt announced a change of license
735 which, when carried out, should make Qt free software. There is no way
736 to be sure, but I think that this was partly due to the community's
737 firm response to the problem that Qt posed when it was non-free. (The
738 new license is inconvenient and inequitable, so it remains desirable
741 [Subsequent note: in September 2000, Qt was rereleased under the GNU
742 GPL, which essentially solved this problem.]
744 How will we respond to the next tempting non-free library? Will the
745 whole community understand the need to stay out of the trap? Or will
746 many of us give up freedom for convenience, and produce a major
747 problem? Our future depends on our philosophy.
751 The worst threat we face comes from software patents, which can put
752 algorithms and features off limits to free software for up to twenty
753 years. The LZW compression algorithm patents were applied for in 1983,
754 and we still cannot release free software to produce proper compressed
755 GIFs. In 1998, a free program to produce MP3 compressed audio was
756 removed from distribution under threat of a patent suit.
758 There are ways to cope with patents: we can search for evidence that a
759 patent is invalid, and we can look for alternative ways to do a job.
760 But each of these methods works only sometimes; when both fail, a
761 patent may force all free software to lack some feature that users
762 want. What will we do when this happens?
764 Those of us who value free software for freedom's sake will stay with
765 free software anyway. We will manage to get work done without the
766 patented features. But those who value free software because they
767 expect it to be techically superior are likely to call it a failure
768 when a patent holds it back. Thus, while it is useful to talk about
769 the practical effectiveness of the "cathedral" model of development,
770 and the reliability and power of some free software, we must not stop
771 there. We must talk about freedom and principle.
775 The biggest deficiency in our free operating systems is not in the
776 software--it is the lack of good free manuals that we can include in
777 our systems. Documentation is an essential part of any software
778 package; when an important free software package does not come with a
779 good free manual, that is a major gap. We have many such gaps today.
781 Free documentation, like free software, is a matter of freedom, not
782 price. The criterion for a free manual is pretty much the same as for
783 free software: it is a matter of giving all users certain freedoms.
784 Redistribution (including commercial sale) must be permitted, on-line
785 and on paper, so that the manual can accompany every copy of the
788 Permission for modification is crucial too. As a general rule, I don't
789 believe that it is essential for people to have permission to modify
790 all sorts of articles and books. For example, I don't think you or I
791 are obliged to give permission to modify articles like this one, which
792 describe our actions and our views.
794 But there is a particular reason why the freedom to modify is crucial
795 for documentation for free software. When people exercise their right
796 to modify the software, and add or change its features, if they are
797 conscientious they will change the manual too--so they can provide
798 accurate and usable documentation with the modified program. A manual
799 which does not allow programmers to be conscientious and finish the
800 job, does not fill our community's needs.
802 Some kinds of limits on how modifications are done pose no problem.
803 For example, requirements to preserve the original author's copyright
804 notice, the distribution terms, or the list of authors, are ok. It is
805 also no problem to require modified versions to include notice that
806 they were modified, even to have entire sections that may not be
807 deleted or changed, as long as these sections deal with nontechnical
808 topics. These kinds of restrictions are not a problem because they
809 don't stop the conscientious programmer from adapting the manual to
810 fit the modified program. In other words, they don't block the free
811 software community from making full use of the manual.
813 However, it must be possible to modify all the *technical* content of
814 the manual, and then distribute the result in all the usual media,
815 through all the usual channels; otherwise, the restrictions do
816 obstruct the community, the manual is not free, and we need another
819 Will free software developers have the awareness and determination to
820 produce a full spectrum of free manuals? Once again, our future
821 depends on philosophy.
823 We must talk about freedom
825 Estimates today are that there are ten million users of GNU/Linux
826 systems such as Debian GNU/Linux and Red Hat Linux. Free software has
827 developed such practical advantages that users are flocking to it for
828 purely practical reasons.
830 The good consequences of this are evident: more interest in developing
831 free software, more customers for free software businesses, and more
832 ability to encourage companies to develop commercial free software
833 instead of proprietary software products.
835 But interest in the software is growing faster than awareness of the
836 philosophy it is based on, and this leads to trouble. Our ability to
837 meet the challenges and threats described above depends on the will to
838 stand firm for freedom. To make sure our community has this will, we
839 need to spread the idea to the new users as they come into the
842 But we are failing to do so: the efforts to attract new users into our
843 community are far outstripping the efforts to teach them the civics of
844 our community. We need to do both, and we need to keep the two efforts
849 Teaching new users about freedom became more difficult in 1998, when a
850 part of the community decided to stop using the term "free software"
851 and say "open source software" instead.
853 Some who favored this term aimed to avoid the confusion of "free" with
854 "gratis"--a valid goal. Others, however, aimed to set aside the spirit
855 of principle that had motivated the free software movement and the GNU
856 project, and to appeal instead to executives and business users, many
857 of whom hold an ideology that places profit above freedom, above
858 community, above principle. Thus, the rhetoric of "open source"
859 focuses on the potential to make high quality, powerful software, but
860 shuns the ideas of freedom, community, and principle.
862 The "Linux" magazines are a clear example of this--they are filled
863 with advertisements for proprietary software that works with
864 GNU/Linux. When the next Motif or Qt appears, will these magazines
865 warn programmers to stay away from it, or will they run ads for it?
867 The support of business can contribute to the community in many ways;
868 all else being equal, it is useful. But winning their support by
869 speaking even less about freedom and principle can be disastrous; it
870 makes the previous imbalance between outreach and civics education
873 "Free software" and "open source" describe the same category of
874 software, more or less, but say different things about the software,
875 and about values. The GNU Project continues to use the term "free
876 software", to express the idea that freedom, not just technology, is
881 Yoda's philosophy ("There is no `try'") sounds neat, but it doesn't
882 work for me. I have done most of my work while anxious about whether I
883 could do the job, and unsure that it would be enough to achieve the
884 goal if I did. But I tried anyway, because there was no one but me
885 between the enemy and my city. Surprising myself, I have sometimes
888 Sometimes I failed; some of my cities have fallen. Then I found
889 another threatened city, and got ready for another battle. Over time,
890 I've learned to look for threats and put myself between them and my
891 city, calling on other hackers to come and join me.
893 Nowadays, often I'm not the only one. It is a relief and a joy when I
894 see a regiment of hackers digging in to hold the line, and I realize,
895 this city may survive--for now. But the dangers are greater each year,
896 and now Microsoft has explicitly targeted our community. We can't take
897 the future of freedom for granted. Don't take it for granted! If you
898 want to keep your freedom, you must be prepared to defend it.
900 Copyright (C) 1998 Richard Stallman
902 Verbatim copying and distribution of this entire article is permitted
903 in any medium, provided this notice is preserved.