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Clarify that the four freedoms apply to any and all users,
and that requiring users to pay to exercise some of these freedoms is
a way of denying them.

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3 <title>What is free software?
4 - GNU Project - Free Software Foundation</title>
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16
17 <h2>What is free software?</h2>
18
19 <div class="article">
20 <h3>The Free Software Definition</h3>
21
22 <blockquote class="note" id="fsf-licensing"><p style="font-size: 80%">
23 Have a question about free software licensing not answered here?
24 See our other <a href="http://www.fsf.org/licensing">licensing resources</a>,
25 and if necessary contact the FSF Compliance Lab
26 at <a href="mailto:licensing@fsf.org">licensing@fsf.org</a>.</p>
27 </blockquote>
28
29 <div class="comment">
30 <p>
31 The free software definition presents the criteria for whether a
32 particular software program qualifies as free software. From time to
33 time we revise this definition, to clarify it or to resolve questions
34 about subtle issues. See the <a href="#History">History section</a>
35 below for a list of changes that affect the definition of free
36 software.
37 </p>
38
39 <p>
40 &ldquo;Open source&rdquo; is something different: it has a very
41 different philosophy based on different values. Its practical
42 definition is different too, but nearly all open source programs are
43 in fact free. We explain the
44 difference in <a href="/philosophy/open-source-misses-the-point.html">
45 Why &ldquo;Open Source&rdquo; misses the point of Free Software</a>.
46 </p>
47 </div>
48
49 <p>
50 &ldquo;Free software&rdquo; means software that respects users'
51 freedom and community. Roughly, it means that <b>the users have the
52 freedom to run, copy, distribute, study, change and improve the
53 software</b>. Thus, &ldquo;free software&rdquo; is a matter of
54 liberty, not price. To understand the concept, you should think of
55 &ldquo;free&rdquo; as in &ldquo;free speech,&rdquo; not as in
56 &ldquo;free beer&rdquo;. We sometimes call it &ldquo;libre
57 software,&rdquo; borrowing the French or Spanish word for
58 &ldquo;free&rdquo; as in freedom, to show we do not mean the software
59 is gratis.
60 </p>
61
62 <p>
63 We campaign for these freedoms because everyone deserves them. With
64 these freedoms, the users (both individually and collectively) control
65 the program and what it does for them. When users don't control the
66 program, we call it a &ldquo;nonfree&rdquo; or
67 &ldquo;proprietary&rdquo; program. The nonfree program controls the
68 users, and the developer controls the program; this makes the
69 program <a href="/philosophy/free-software-even-more-important.html">
70 an instrument of unjust power</a>.
71 </p>
72
73 <h4> The four essential freedoms</h4>
74
75 <p>
76 A program is free software if the program's users have the
77 four essential freedoms: <a href="#f1">[1]</a>
78 </p>
79
80 <ul class="important">
81 <li>The freedom to run the program as you wish,
82 for any purpose (freedom 0).</li>
83 <li>The freedom to study how the program works, and change it so it
84 does your computing as you wish (freedom 1). Access to the source
85 code is a precondition for this.
86 </li>
87 <li>The freedom to redistribute copies so you can help others
88 (freedom 2).
89 </li>
90 <li>The freedom to distribute copies of your modified versions
91 to others (freedom 3). By doing this you can give the whole
92 community a chance to benefit from your changes.
93 Access to the source code is a precondition for this.
94 </li>
95 </ul>
96
97 <p>
98 A program is free software if it gives users adequately all of these
99 freedoms. Otherwise, it is nonfree. While we can distinguish various
100 nonfree distribution schemes in terms of how far they fall short of
101 being free, we consider them all equally unethical.</p>
102
103 <p>In any given scenario, these freedoms must apply to whatever code
104 we plan to make use of, or lead others to make use of. For instance,
105 consider a program A which automatically launches a program B to
106 handle some cases. If we plan to distribute A as it stands, that
107 implies users will need B, so we need to judge whether both A and B
108 are free. However, if we plan to modify A so that it doesn't use B,
109 only A needs to be free; B is not pertinent to that plan.</p>
110
111 <p>
112 &ldquo;Free software&rdquo; does not mean &ldquo;noncommercial&rdquo;. A free
113 program must be available for commercial use, commercial development,
114 and commercial distribution. Commercial development of free software
115 is no longer unusual; such free commercial software is very important.
116 You may have paid money to get copies of free software, or you may have
117 obtained copies at no charge. But regardless of how you got your copies,
118 you always have the freedom to copy and change the software, even to
119 <a href="/philosophy/selling.html">sell copies</a>.
120 </p>
121
122 <p>
123 A free program must offer the four freedoms to any user that obtains a
124 copy of the software, provided the user has complied thus far with the
125 conditions of the free license covering the software. Putting some of
126 the freedoms off limits to some users, or requiring that users pay, in
127 money or in kind, to exercise them, is tantamount to not granting the
128 freedoms in question, and thus renders the program nonfree.
129 </p>
130
131 <p>The rest of this page clarifies certain points about what makes
132 specific freedoms adequate or not.</p>
133
134 <h4>The freedom to run the program as you wish</h4>
135
136 <p>
137 The freedom to run the program means the freedom for any kind of person
138 or organization to use it on any kind of computer system, for any kind of
139 overall job and purpose, without being required to communicate about it
140 with the developer or any other specific entity. In this freedom, it is
141 the <em>user's</em> purpose that matters, not the <em>developer's</em>
142 purpose; you as a user are free to run the program for your purposes,
143 and if you distribute it to someone else, she is then free to run it
144 for her purposes, but you are not entitled to impose your purposes on her.
145 </p>
146
147 <p>
148 The freedom to run the program as you wish means that you are not
149 forbidden or stopped from making it run. This has nothing to do with what
150 functionality the program has, whether it is technically capable of
151 functioning in any given environment, or whether it is useful for any
152 particular computing activity.</p>
153
154 <h4>The freedom to study the source code and make changes</h4>
155
156 <p>
157 In order for freedoms 1 and 3 (the freedom to make changes and the
158 freedom to publish the changed versions) to be meaningful, you must have
159 access to the source code of the program. Therefore, accessibility of
160 source code is a necessary condition for free software. Obfuscated
161 &ldquo;source code&rdquo; is not real source code and does not count
162 as source code.
163 </p>
164
165 <p>
166 Freedom 1 includes the freedom to use your changed version in place of
167 the original. If the program is delivered in a product designed to
168 run someone else's modified versions but refuse to run yours &mdash; a
169 practice known as &ldquo;tivoization&rdquo; or &ldquo;lockdown&rdquo;,
170 or (in its practitioners' perverse terminology) as &ldquo;secure
171 boot&rdquo; &mdash; freedom 1 becomes an empty pretense rather than a
172 practical reality. These binaries are not free
173 software even if the source code they are compiled from is free.
174 </p>
175
176 <p>
177 One important way to modify a program is by merging in available free
178 subroutines and modules. If the program's license says that you
179 cannot merge in a suitably licensed existing module &mdash; for instance, if it
180 requires you to be the copyright holder of any code you add &mdash; then the
181 license is too restrictive to qualify as free.
182 </p>
183
184 <p>
185 Whether a change constitutes an improvement is a subjective matter.
186 If your right to modify a program is limited, in substance, to changes that
187 someone else considers an improvement, that program is not free.
188 </p>
189
190 <h4>The freedom to redistribute if you wish: basic requirements</h4>
191
192 <p>Freedom to distribute (freedoms 2 and 3) means you are free to
193 redistribute copies, either with or without modifications, either
194 gratis or charging a fee for distribution, to
195 <a href="#exportcontrol">anyone anywhere</a>. Being free to do these
196 things means (among other things) that you do not have to ask or pay
197 for permission to do so.
198 </p>
199
200 <p>
201 You should also have the freedom to make modifications and use them
202 privately in your own work or play, without even mentioning that they
203 exist. If you do publish your changes, you should not be required to
204 notify anyone in particular, or in any particular way.
205 </p>
206
207 <p>
208 Freedom 3 includes the freedom to release your modified versions
209 as free software. A free license may also permit other ways of
210 releasing them; in other words, it does not have to be
211 a <a href="/copyleft/copyleft.html">copyleft</a> license. However, a
212 license that requires modified versions to be nonfree does not qualify
213 as a free license.
214 </p>
215
216 <p>
217 The freedom to redistribute copies must include binary or executable
218 forms of the program, as well as source code, for both modified and
219 unmodified versions. (Distributing programs in runnable form is necessary
220 for conveniently installable free operating systems.) It is OK if there
221 is no way to produce a binary or executable form for a certain program
222 (since some languages don't support that feature), but you must have the
223 freedom to redistribute such forms should you find or develop a way to
224 make them.
225 </p>
226
227 <h4>Copyleft</h4>
228
229 <p>
230 Certain kinds of rules about the manner of distributing free
231 software are acceptable, when they don't conflict with the central
232 freedoms. For example, <a href="/copyleft/copyleft.html">copyleft</a>
233 (very simply stated) is the rule that when redistributing the program,
234 you cannot add restrictions to deny other people the central freedoms.
235 This rule does not conflict with the central freedoms; rather it
236 protects them.
237 </p>
238
239 <p>
240 In the GNU project, we use copyleft to protect the four freedoms
241 legally for everyone. We believe there are important reasons why
242 <a href="/philosophy/pragmatic.html">it is better to use
243 copyleft</a>. However,
244 <a href="/philosophy/categories.html#Non-CopyleftedFreeSoftware">
245 noncopylefted free software</a> is ethical
246 too. See <a href="/philosophy/categories.html">Categories of Free
247 Software</a> for a description of how &ldquo;free software,&rdquo;
248 &ldquo;copylefted software&rdquo; and other categories of software
249 relate to each other.
250 </p>
251
252 <h4>Rules about packaging and distribution details</h4>
253
254 <p>
255 Rules about how to package a modified version are acceptable,
256 if they don't substantively limit your freedom to release modified
257 versions, or your freedom to make and use modified versions privately.
258 Thus, it is acceptable for the license to require that you change the
259 name of the modified version, remove a logo, or identify your
260 modifications as yours. As long as these requirements are not so
261 burdensome that they effectively hamper you from releasing your
262 changes, they are acceptable; you're already making other changes to
263 the program, so you won't have trouble making a few more.
264 </p>
265
266 <p>
267 Rules that &ldquo;if you make your version available in this way, you
268 must make it available in that way also&rdquo; can be acceptable too,
269 on the same condition. An example of such an acceptable rule is one
270 saying that if you have distributed a
271 modified version and a previous developer asks for a copy of it, you
272 must send one. (Note that such a rule still leaves you the choice of
273 whether to distribute your version at all.) Rules that require release
274 of source code to the users for versions that you put into public use
275 are also acceptable.
276 </p>
277
278 <p>
279 A special issue arises when a license requires changing the name by
280 which the program will be invoked from other programs. That
281 effectively hampers you from releasing your changed version so that it
282 can replace the original when invoked by those other programs. This
283 sort of requirement is acceptable only if there's a suitable aliasing
284 facility that allows you to specify the original program's name as an
285 alias for the modified version.</p>
286
287 <h4>Export regulations</h4>
288
289 <p>
290 Sometimes government <a id="exportcontrol">export control regulations</a>
291 and trade sanctions can constrain your freedom to distribute copies of
292 programs internationally. Software developers do not have the power to
293 eliminate or override these restrictions, but what they can and must do
294 is refuse to impose them as conditions of use of the program. In this
295 way, the restrictions will not affect activities and people outside the
296 jurisdictions of these governments. Thus, free software licenses
297 must not require obedience to any nontrivial export regulations as a
298 condition of exercising any of the essential freedoms.
299 </p>
300
301 <p>
302 Merely mentioning the existence of export regulations, without making
303 them a condition of the license itself, is acceptable since it does
304 not restrict users. If an export regulation is actually trivial for
305 free software, then requiring it as a condition is not an actual
306 problem; however, it is a potential problem, since a later change in
307 export law could make the requirement nontrivial and thus render the
308 software nonfree.
309 </p>
310
311 <h4>Legal considerations</h4>
312
313 <p>
314 In order for these freedoms to be real, they must be permanent and
315 irrevocable as long as you do nothing wrong; if the developer of the
316 software has the power to revoke the license, or retroactively add
317 restrictions to its terms, without your doing anything wrong to give
318 cause, the software is not free.
319 </p>
320
321 <p>
322 A free license may not require compliance with the license of a
323 nonfree program. Thus, for instance, if a license requires you to
324 comply with the licenses of &ldquo;all the programs you use&rdquo;, in
325 the case of a user that runs nonfree programs this would require
326 compliance with the licenses of those nonfree programs; that makes the
327 license nonfree.
328 </p>
329
330 <p>
331 It is acceptable for a free license to specify which jurisdiction's
332 law applies, or where litigation must be done, or both.
333 </p>
334
335 <h4>Contract-based licenses</h4>
336
337 <p>
338 Most free software licenses are based on copyright, and there are limits
339 on what kinds of requirements can be imposed through copyright. If a
340 copyright-based license respects freedom in the ways described above, it
341 is unlikely to have some other sort of problem that we never anticipated
342 (though this does happen occasionally). However, some free software
343 licenses are based on contracts, and contracts can impose a much larger
344 range of possible restrictions. That means there are many possible ways
345 such a license could be unacceptably restrictive and nonfree.
346 </p>
347
348 <p>
349 We can't possibly list all the ways that might happen. If a
350 contract-based license restricts the user in an unusual way that
351 copyright-based licenses cannot, and which isn't mentioned here as
352 legitimate, we will have to think about it, and we will probably conclude
353 it is nonfree.
354 </p>
355
356 <h4>Use the right words when talking about free software</h4>
357
358 <p>
359 When talking about free software, it is best to avoid using terms
360 like &ldquo;give away&rdquo; or &ldquo;for free,&rdquo; because those terms imply that
361 the issue is about price, not freedom. Some common terms such
362 as &ldquo;piracy&rdquo; embody opinions we hope you won't endorse. See
363 <a href="/philosophy/words-to-avoid.html">Confusing Words and Phrases that
364 are Worth Avoiding</a> for a discussion of these terms. We also have
365 a list of proper <a href="/philosophy/fs-translations.html">translations of
366 &ldquo;free software&rdquo;</a> into various languages.
367 </p>
368
369 <h4>How we interpret these criteria</h4>
370
371 <p>
372 Finally, note that criteria such as those stated in this free software
373 definition require careful thought for their interpretation. To decide
374 whether a specific software license qualifies as a free software license,
375 we judge it based on these criteria to determine whether it fits their
376 spirit as well as the precise words. If a license includes unconscionable
377 restrictions, we reject it, even if we did not anticipate the issue
378 in these criteria. Sometimes a license requirement raises an issue
379 that calls for extensive thought, including discussions with a lawyer,
380 before we can decide if the requirement is acceptable. When we reach
381 a conclusion about a new issue, we often update these criteria to make
382 it easier to see why certain licenses do or don't qualify.
383 </p>
384
385 <h4>Get help with free licenses</h4>
386
387 <p>
388 If you are interested in whether a specific license qualifies as a free
389 software license, see our <a href="/licenses/license-list.html">list
390 of licenses</a>. If the license you are concerned with is not
391 listed there, you can ask us about it by sending us email at
392 <a href="mailto:licensing@gnu.org">&lt;licensing@gnu.org&gt;</a>.
393 </p>
394
395 <p>
396 If you are contemplating writing a new license, please contact the
397 Free Software Foundation first by writing to that address. The
398 proliferation of different free software licenses means increased work
399 for users in understanding the licenses; we may be able to help you
400 find an existing free software license that meets your needs.
401 </p>
402
403 <p>
404 If that isn't possible, if you really need a new license, with our
405 help you can ensure that the license really is a free software license
406 and avoid various practical problems.
407 </p>
408
409 <h3 id="beyond-software">Beyond Software</h3>
410
411 <p>
412 <a href="/philosophy/free-doc.html">Software manuals must be free</a>,
413 for the same reasons that software must be free, and because the
414 manuals are in effect part of the software.
415 </p>
416
417 <p>
418 The same arguments also make sense for other kinds of works of
419 practical use &mdash; that is to say, works that embody useful knowledge,
420 such as educational works and reference
421 works. <a href="http://wikipedia.org">Wikipedia</a> is the best-known
422 example.
423 </p>
424
425 <p>
426 Any kind of work <em>can</em> be free, and the definition of free software
427 has been extended to a definition of <a href="http://freedomdefined.org/">
428 free cultural works</a> applicable to any kind of works.
429 </p>
430
431 <h3 id="open-source">Open Source?</h3>
432
433 <p>
434 Another group uses the term &ldquo;open source&rdquo; to mean
435 something close (but not identical) to &ldquo;free software&rdquo;. We
436 prefer the term &ldquo;free software&rdquo; because, once you have heard that
437 it refers to freedom rather than price, it calls to mind freedom. The
438 word &ldquo;open&rdquo; <a href="/philosophy/open-source-misses-the-point.html">
439 never refers to freedom</a>.
440 </p>
441 </div>
442
443 <h3 id="History">History</h3>
444
445 <p>From time to time we revise this Free Software Definition. Here is
446 the list of substantive changes, along with links to show exactly what
447 was changed.</p>
448
449 <ul>
450
451 <li><a href="http://web.cvs.savannah.gnu.org/viewvc/www/philosophy/free-sw.html?root=www&amp;r1=1.162&amp;r2=1.163">Version
452 1.163</a>: Clarify that the four freedoms apply to any and all users,
453 and that requiring users to pay to exercise some of these freedoms is
454 a way of denying them.</li>
455
456 <li><a href="http://web.cvs.savannah.gnu.org/viewvc/www/philosophy/free-sw.html?root=www&amp;r1=1.152&amp;r2=1.153">Version
457 1.153</a>: Clarify that freedom to run the program means nothing stops
458 you from making it run.</li>
459
460 <li><a href="http://web.cvs.savannah.gnu.org/viewvc/www/philosophy/free-sw.html?root=www&amp;r1=1.140&amp;r2=1.141">Version
461 1.141</a>: Clarify which code needs to be free.</li>
462
463 <li><a href="http://web.cvs.savannah.gnu.org/viewvc/www/philosophy/free-sw.html?root=www&amp;r1=1.134&amp;r2=1.135">Version
464 1.135</a>: Say each time that freedom 0 is the freedom to run the program
465 as you wish.</li>
466
467 <li><a href="http://web.cvs.savannah.gnu.org/viewvc/www/philosophy/free-sw.html?root=www&amp;r1=1.133&amp;r2=1.134">Version
468 1.134</a>: Freedom 0 is not a matter of the program's functionality.</li>
469
470 <li><a href="http://web.cvs.savannah.gnu.org/viewvc/www/philosophy/free-sw.html?root=www&amp;r1=1.130&amp;r2=1.131">Version
471 1.131</a>: A free license may not require compliance with a nonfree license
472 of another program.</li>
473
474 <li><a href="http://web.cvs.savannah.gnu.org/viewvc/www/philosophy/free-sw.html?root=www&amp;r1=1.128&amp;r2=1.129">Version
475 1.129</a>: State explicitly that choice of law and choice of forum
476 specifications are allowed. (This was always our policy.)</li>
477
478 <li><a href="http://web.cvs.savannah.gnu.org/viewvc/www/philosophy/free-sw.html?root=www&amp;r1=1.121&amp;r2=1.122">Version
479 1.122</a>: An export control requirement is a real problem if the
480 requirement is nontrivial; otherwise it is only a potential problem.</li>
481
482 <li><a href="http://web.cvs.savannah.gnu.org/viewvc/www/philosophy/free-sw.html?root=www&amp;r1=1.117&amp;r2=1.118">Version
483 1.118</a>: Clarification: the issue is limits on your right to modify,
484 not on what modifications you have made. And modifications are not limited
485 to &ldquo;improvements&rdquo;</li>
486
487 <li><a href="http://web.cvs.savannah.gnu.org/viewvc/www/philosophy/free-sw.html?root=www&amp;r1=1.110&amp;r2=1.111">Version
488 1.111</a>: Clarify 1.77 by saying that only
489 retroactive <em>restrictions</em> are unacceptable. The copyright
490 holders can always grant additional <em>permission</em> for use of the
491 work by releasing the work in another way in parallel.</li>
492
493 <li><a href="http://web.cvs.savannah.gnu.org/viewvc/www/philosophy/free-sw.html?root=www&amp;r1=1.104&amp;r2=1.105">Version
494 1.105</a>: Reflect, in the brief statement of freedom 1, the point
495 (already stated in version 1.80) that it includes really using your modified
496 version for your computing.</li>
497
498 <li><a href="http://web.cvs.savannah.gnu.org/viewvc/www/philosophy/free-sw.html?root=www&amp;r1=1.91&amp;r2=1.92">Version
499 1.92</a>: Clarify that obfuscated code does not qualify as source code.</li>
500
501 <li><a href="http://web.cvs.savannah.gnu.org/viewvc/www/philosophy/free-sw.html?root=www&amp;r1=1.89&amp;r2=1.90">Version
502 1.90</a>: Clarify that freedom 3 means the right to distribute copies
503 of your own modified or improved version, not a right to participate
504 in someone else's development project.</li>
505
506 <li><a href="http://web.cvs.savannah.gnu.org/viewvc/www/philosophy/free-sw.html?root=www&amp;r1=1.88&amp;r2=1.89">Version
507 1.89</a>: Freedom 3 includes the right to release modified versions as
508 free software.</li>
509
510 <li><a href="http://web.cvs.savannah.gnu.org/viewvc/www/philosophy/free-sw.html?root=www&amp;r1=1.79&amp;r2=1.80">Version
511 1.80</a>: Freedom 1 must be practical, not just theoretical;
512 i.e., no tivoization.</li>
513
514 <li><a href="http://web.cvs.savannah.gnu.org/viewvc/www/philosophy/free-sw.html?root=www&amp;r1=1.76&amp;r2=1.77">Version
515 1.77</a>: Clarify that all retroactive changes to the license are
516 unacceptable, even if it's not described as a complete
517 replacement.</li>
518
519 <li><a href="http://web.cvs.savannah.gnu.org/viewvc/www/philosophy/free-sw.html?root=www&amp;r1=1.73&amp;r2=1.74">Version
520 1.74</a>: Four clarifications of points not explicit enough, or stated
521 in some places but not reflected everywhere:
522 <ul>
523 <li>"Improvements" does not mean the license can
524 substantively limit what kinds of modified versions you can release.
525 Freedom 3 includes distributing modified versions, not just changes.</li>
526 <li>The right to merge in existing modules
527 refers to those that are suitably licensed.</li>
528 <li>Explicitly state the conclusion of the point about export controls.</li>
529 <li>Imposing a license change constitutes revoking the old license.</li>
530 </ul>
531 </li>
532
533 <li><a href="http://web.cvs.savannah.gnu.org/viewvc/www/philosophy/free-sw.html?root=www&amp;r1=1.56&amp;r2=1.57">Version
534 1.57</a>: Add &quot;Beyond Software&quot; section.</li>
535
536 <li><a href="http://web.cvs.savannah.gnu.org/viewvc/www/philosophy/free-sw.html?root=www&amp;r1=1.45&amp;r2=1.46">Version
537 1.46</a>: Clarify whose purpose is significant in the freedom to run
538 the program for any purpose.</li>
539
540 <li><a href="http://web.cvs.savannah.gnu.org/viewvc/www/philosophy/free-sw.html?root=www&amp;r1=1.40&amp;r2=1.41">Version
541 1.41</a>: Clarify wording about contract-based licenses.</li>
542
543 <li><a href="http://web.cvs.savannah.gnu.org/viewvc/www/philosophy/free-sw.html?root=www&amp;r1=1.39&amp;r2=1.40">Version
544 1.40</a>: Explain that a free license must allow to you use other
545 available free software to create your modifications.</li>
546
547 <li><a href="http://web.cvs.savannah.gnu.org/viewvc/www/philosophy/free-sw.html?root=www&amp;r1=1.38&amp;r2=1.39">Version
548 1.39</a>: Note that it is acceptable for a license to require you to
549 provide source for versions of the software you put into public
550 use.</li>
551
552 <li><a href="http://web.cvs.savannah.gnu.org/viewvc/www/philosophy/free-sw.html?root=www&amp;r1=1.30&amp;r2=1.31">Version
553 1.31</a>: Note that it is acceptable for a license to require you to
554 identify yourself as the author of modifications. Other minor
555 clarifications throughout the text.</li>
556
557 <li><a href="http://web.cvs.savannah.gnu.org/viewvc/www/philosophy/free-sw.html?root=www&amp;r1=1.22&amp;r2=1.23">Version
558 1.23</a>: Address potential problems related to contract-based
559 licenses.</li>
560
561 <li><a href="http://web.cvs.savannah.gnu.org/viewvc/www/philosophy/free-sw.html?root=www&amp;r1=1.15&amp;r2=1.16">Version
562 1.16</a>: Explain why distribution of binaries is important.</li>
563
564 <li><a href="http://web.cvs.savannah.gnu.org/viewvc/www/philosophy/free-sw.html?root=www&amp;r1=1.10&amp;r2=1.11">Version
565 1.11</a>: Note that a free license may require you to send a copy of
566 versions you distribute to previous developers on request.</li>
567
568 </ul>
569
570 <p>There are gaps in the version numbers shown above because there are
571 other changes in this page that do not affect the definition or its
572 interpretations. For instance, the list does not include changes in
573 asides, formatting, spelling, punctuation, or other parts of the page.
574 You can review the complete list of changes to the page through
575 the <a href="http://web.cvs.savannah.gnu.org/viewvc/www/philosophy/free-sw.html?root=www&amp;view=log">cvsweb
576 interface</a>.</p>
577
578 <h3 style="font-size:1em">Footnote</h3>
579 <ol>
580 <li id="f1">The reason they are numbered 0, 1, 2 and 3 is historical. Around
581 1990 there were three freedoms, numbered 1, 2 and 3. Then we realized that
582 the freedom to run the program needed to be mentioned explicitly.
583 It was clearly more basic than the other three, so it properly should
584 precede them. Rather than renumber the others, we made it freedom&nbsp;0.</li>
585 </ol>
586
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588 <!--#include virtual="/server/footer.html" -->
589 <div id="footer">
590 <div class="unprintable">
591
592 <p>Please send general FSF &amp; GNU inquiries to
593 <a href="mailto:gnu@gnu.org">&lt;gnu@gnu.org&gt;</a>.
594 There are also <a href="/contact/">other ways to contact</a>
595 the FSF. Broken links and other corrections or suggestions can be sent
596 to <a href="mailto:webmasters@gnu.org">&lt;webmasters@gnu.org&gt;</a>.</p>
597
598 <p><!-- TRANSLATORS: Ignore the original text in this paragraph,
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600
601 We work hard and do our best to provide accurate, good quality
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604 to <a href="mailto:web-translators@gnu.org">
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606
607 <p>For information on coordinating and submitting translations of
608 our web pages, see <a
609 href="/server/standards/README.translations.html">Translations
610 README</a>. -->
611 Please see the <a
612 href="/server/standards/README.translations.html">Translations
613 README</a> for information on coordinating and submitting translations
614 of this article.</p>
615 </div>
616
617 <!-- Regarding copyright, in general, standalone pages (as opposed to
618 files generated as part of manuals) on the GNU web server should
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624
625 If you wish to list earlier years, that is ok too.
626 Either "2001, 2002, 2003" or "2001-2003" are ok for specifying
627 years, as long as each year in the range is in fact a copyrightable
628 year, i.e., a year in which the document was published (including
629 being publicly visible on the web or in a revision control system).
630
631 There is more detail about copyright years in the GNU Maintainers
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633
634 <p>Copyright &copy; 1996, 2002, 2004-2007, 2009-2018
635 Free Software Foundation, Inc.</p>
636
637 <p>This page is licensed under a <a rel="license"
638 href="http://creativecommons.org/licenses/by-nd/4.0/">Creative
639 Commons Attribution-NoDerivatives 4.0 International License</a>.</p>
640
641 <!--#include virtual="/server/bottom-notes.html" -->
642
643 <p class="unprintable">Updated:
644 <!-- timestamp start -->
645 $Date: 2018/12/15 14:02:38 $
646 <!-- timestamp end -->
647 </p>
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