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4  <html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en">  - GNU Project - Free Software Foundation</title>
   
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8    
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11    
12    <h2>What is free software?</h2>
13    
14  <h3>The Free Software Definition</h3>  <h3>The Free Software Definition</h3>
15    
16    <blockquote>
17  <p>  <p>
18  <a href="/graphics/philosophicalgnu.html"><img src="/graphics/philosophical-gnu-sm.jpg" alt=" [image of a Philosophical Gnu] " width="160" height="200" /></a>  The free software definition presents the criteria for whether a
19    particular software program qualifies as free software.  From time to
20    time we revise this definition, to clarify it or to resolve questions
21    about subtle issues.  See the <a href="#History">History section</a>
22    below for a list of changes that affect the definition of free
23    software.
24  </p>  </p>
25    </blockquote>
26    
27  <p>  <p>
28  We maintain this free software definition to show clearly what must be  &ldquo;Free software&rdquo; means software that respects users'
29  true about a particular software program for it to be considered  freedom and community.  Roughly, it means that <b>the users have the
30  free software.</p>  freedom to run, copy, distribute, study, change and improve the
31    software</b>.  Thus, &ldquo;free software&rdquo; is a matter of
32    liberty, not price.  To understand the concept, you should think of
33    &ldquo;free&rdquo; as in &ldquo;free speech,&rdquo; not as in
34    &ldquo;free beer&rdquo;.
35    </p>
36    
37  <p>  <p>
38  ``Free software'' is a matter of liberty, not price.  To understand the  We campaign for these freedoms because everyone deserves them.  With
39  concept, you should think of ``free'' as in ``free speech,'' not as in  these freedoms, the users (both individually and collectively) control
40  ``free beer.''</p>  the program and what it does for them.  When users don't control the
41    program, we call it a &ldquo;nonfree&rdquo; or
42    &ldquo;proprietary&rdquo; program.  The nonfree program controls the
43    users, and the developer controls the program; which makes the
44    program <a href="/philosophy/free-software-even-more-important.html">
45    an instrument of unjust power</a>.
46    </p>
47    
48  <p>  <p>
49  Free software is a matter of the users' freedom to run, copy,  A program is free software if the program's users have the
50  distribute, study, change and improve the software.  More precisely,  four essential freedoms:
51  it refers to four kinds of freedom, for the users of the software:</p>  </p>
52    
53  <ul>  <ul>
54    <li>The freedom to run the program, for any purpose (freedom 0).</li>    <li>The freedom to run the program, for any purpose (freedom 0).</li>
55    <li>The freedom to study how the program works, and adapt it to your needs    <li>The freedom to study how the program works, and change it so it
56        (freedom 1).   Access to the source code is a precondition for this.</li>        does your computing as you wish (freedom 1). Access to the source
57          code is a precondition for this.
58      </li>
59    <li>The freedom to redistribute copies so you can help your neighbor    <li>The freedom to redistribute copies so you can help your neighbor
60        (freedom 2).</li>        (freedom 2).
61    <li>The freedom to improve the program, and release your improvements    </li>
62       to the public, so that the whole community benefits    <li>The freedom to distribute copies of your modified versions
63        (freedom 3).   Access to the source code is a precondition for this.</li>        to others (freedom 3).  By doing this you can give the whole
64          community a chance to benefit from your changes.
65          Access to the source code is a precondition for this.
66      </li>
67  </ul>  </ul>
68    
69  <p>  <p>
70  A program is free software if users have all of these freedoms.  A program is free software if it gives users adequately all of these
71  Thus, you should be free to redistribute copies, either with or  freedoms.  Otherwise, it is nonfree.  While we can distinguish various
72  without modifications, either gratis or charging a fee for  nonfree distribution schemes in terms of how far they fall short of
73  distribution, to <a href="#exportcontrol">anyone anywhere</a>.  Being  being free, we consider them all equally unethical.</p>
74  free to do these things means (among other things) that you do not  
75  have to ask or pay for permission.</p>  <p>The rest of this page clarifies certain points about what makes
76    specific freedoms adequate or not.</p>
77    
78    <p>Freedom to distribute (freedoms 2 and 3) means you are free to
79    redistribute copies, either with or without modifications, either
80    gratis or charging a fee for distribution, to
81    <a href="#exportcontrol">anyone anywhere</a>.  Being free to do these
82    things means (among other things) that you do not have to ask or pay
83    for permission to do so.
84    </p>
85    
86  <p>  <p>
87  You should also have the freedom to make modifications and use them  You should also have the freedom to make modifications and use them
88  privately in your own work or play, without even mentioning that they  privately in your own work or play, without even mentioning that they
89  exist.  If you do publish your changes, you should not be required to  exist.  If you do publish your changes, you should not be required to
90  notify anyone in particular, or in any particular way.</p>  notify anyone in particular, or in any particular way.
91    </p>
92    
93  <p>  <p>
94  The freedom to use a program means the freedom for any kind of person  The freedom to run the program means the freedom for any kind of person
95  or organization to use it on any kind of computer system, for any kind  or organization to use it on any kind of computer system, for any kind of
96  of overall job, and without being required to communicate subsequently  overall job and purpose, without being required to communicate about it
97  with the developer or any other specific entity.</p>  with the developer or any other specific entity.  In this freedom, it is
98    the <em>user's</em> purpose that matters, not the <em>developer's</em>
99    purpose; you as a user are free to run the program for your purposes,
100    and if you distribute it to someone else, she is then free to run it
101    for her purposes, but you are not entitled to impose your purposes on her.
102    </p>
103    
104  <p>  <p>
105  The freedom to redistribute copies must include binary or executable  The freedom to redistribute copies must include binary or executable
106  forms of the program, as well as source code, for both modified and  forms of the program, as well as source code, for both modified and
107  unmodified versions.  (Distributing programs in runnable form is  unmodified versions.  (Distributing programs in runnable form is necessary
108  necessary for conveniently installable free operating systems.)  It is  for conveniently installable free operating systems.)  It is OK if there
109  ok if there is no way to produce a binary or executable form for a  is no way to produce a binary or executable form for a certain program
110  certain program (since some languages don't support that feature), but  (since some languages don't support that feature), but you must have the
111  you must have the freedom to redistribute such forms should you find  freedom to redistribute such forms should you find or develop a way to
112  or develop a way to make them.</p>  make them.
113  <p>  </p>
114  In order for the freedoms to make changes, and to publish improved  
115  versions, to be meaningful, you must have access to the source code of  <p>
116  the program.  Therefore, accessibility of source code is a necessary  In order for freedoms 1 and 3 (the freedom to make changes and the
117  condition for free software.</p>  freedom to publish the changed versions) to be meaningful, you must have
118  <p>  access to the source code of the program.  Therefore, accessibility of
119  In order for these freedoms to be real, they must be irrevocable as  source code is a necessary condition for free software.  Obfuscated
120  long as you do nothing wrong; if the developer of the software has the  &ldquo;source code&rdquo; is not real source code and does not count
121  power to revoke the license, without your doing anything to give  as source code.
122  cause, the software is not free.</p>  </p>
123    
124    <p>
125    Freedom 1 includes the freedom to use your changed version in place of
126    the original.  If the program is delivered in a product designed to
127    run someone else's modified versions but refuse to run yours &mdash; a
128    practice known as &ldquo;tivoization&rdquo; or &ldquo;lockdown&rdquo;,
129    or (in its practitioners' perverse terminology) as &ldquo;secure
130    boot&rdquo; &mdash; freedom 1 becomes a theoretical fiction rather
131    than a practical freedom.  This is not sufficient.  In other words,
132    these binaries are not free software even if the source code they are
133    compiled from is free.
134    </p>
135    
136    <p>
137    One important way to modify a program is by merging in available free
138    subroutines and modules.  If the program's license says that you
139    cannot merge in a suitably licensed existing module &mdash; for instance, if it
140    requires you to be the copyright holder of any code you add &mdash; then the
141    license is too restrictive to qualify as free.
142    </p>
143    
144    <p>
145    Freedom 3 includes the freedom to release your modified versions
146    as free software.  A free license may also permit other ways of
147    releasing them; in other words, it does not have to be
148    a <a href="/copyleft/copyleft.html">copyleft</a> license.  However, a
149    license that requires modified versions to be nonfree does not qualify
150    as a free license.
151    </p>
152    
153    <p>
154    In order for these freedoms to be real, they must be permanent and
155    irrevocable as long as you do nothing wrong; if the developer of the
156    software has the power to revoke the license, or retroactively add
157    restrictions to its terms, without your doing anything wrong to give
158    cause, the software is not free.
159    </p>
160    
161  <p>  <p>
162  However, certain kinds of rules about the manner of distributing free  However, certain kinds of rules about the manner of distributing free
163  software are acceptable, when they don't conflict with the central  software are acceptable, when they don't conflict with the central
164  freedoms.  For example, copyleft (very simply stated) is the rule that  freedoms.  For example, copyleft (very simply stated) is the rule that
165  when redistributing the program, you cannot add restrictions to deny  when redistributing the program, you cannot add restrictions to deny
166  other people the central freedoms.  This rule does not conflict with  other people the central freedoms.  This rule does not conflict with
167  the central freedoms; rather it protects them.</p>  the central freedoms; rather it protects them.
168    </p>
169    
170    <p>
171    &ldquo;Free software&rdquo; does not mean &ldquo;noncommercial&rdquo;.  A free
172    program must be available for commercial use, commercial development,
173    and commercial distribution.  Commercial development of free software
174    is no longer unusual; such free commercial software is very important.
175    You may have paid money to get copies of free software, or you may have
176    obtained copies at no charge.  But regardless of how you got your copies,
177    you always have the freedom to copy and change the software, even to
178    <a href="/philosophy/selling.html">sell copies</a>.
179    </p>
180    
181    <p>
182    Whether a change constitutes an improvement is a subjective matter.
183    If your right to modify a program is limited, in substance, to changes that
184    someone else considers an improvement, that program is not free.
185    </p>
186    
187    <p>
188    However, rules about how to package a modified version are acceptable,
189    if they don't substantively limit your freedom to release modified
190    versions, or your freedom to make and use modified versions privately.
191    Thus, it is acceptable for the license to require that you change the
192    name of the modified version, remove a logo, or identify your
193    modifications as yours.  As long as these requirements are not so
194    burdensome that they effectively hamper you from releasing your
195    changes, they are acceptable; you're already making other changes to
196    the program, so you won't have trouble making a few more.
197    </p>
198    
199    <p>
200    Rules that &ldquo;if you make your version available in this way, you
201    must make it available in that way also&rdquo; can be acceptable too,
202    on the same condition.  An example of such an acceptable rule is one
203    saying that if you have distributed a
204    modified version and a previous developer asks for a copy of it, you
205    must send one.  (Note that such a rule still leaves you the choice of
206    whether to distribute your version at all.)  Rules that require release
207    of source code to the users for versions that you put into public use
208    are also acceptable.
209    </p>
210    
211    <p>
212    A special issue arises when a license requires changing the name by
213    which the program will be invoked from other programs.  That
214    effectively hampers you from releasing your changed version so that it
215    can replace the original when invoked by those other programs.  This
216    sort of requirement is acceptable only if there's a suitable aliasing
217    facility that allows you to specify the original program's name as an
218    alias for the modified version.</p>
219    
220    <p>
221    In the GNU project, we use
222    <a href="/copyleft/copyleft.html">copyleft</a>
223    to protect these freedoms legally for everyone.  But
224    <a href="/philosophy/categories.html#Non-CopyleftedFreeSoftware">noncopylefted
225    free software</a> also exists.  We believe there are important reasons why
226    <a href="/philosophy/pragmatic.html">it is better to use copyleft</a>,
227    but if your program is noncopylefted free software, it is still basically
228    ethical. (See <a href="/philosophy/categories.html">Categories of Free Software</a> for a description of how &ldquo;free software,&rdquo; &ldquo;copylefted software&rdquo; and other categories of software relate to each other.)
229    </p>
230    
231    <p>
232    Sometimes government <a id="exportcontrol">export control regulations</a>
233    and trade sanctions can constrain your freedom to distribute copies of
234    programs internationally.  Software developers do not have the power to
235    eliminate or override these restrictions, but what they can and must do
236    is refuse to impose them as conditions of use of the program.  In this
237    way, the restrictions will not affect activities and people outside the
238    jurisdictions of these governments.  Thus, free software licenses
239    must not require obedience to any nontrivial export regulations as a
240    condition of exercising any of the essential freedoms.
241    </p>
242    
243    <p>
244    Merely mentioning the existence of export regulations, without making
245    them a condition of the license itself, is acceptable since it does
246    not restrict users.  If an export regulation is actually trivial for
247    free software, then requiring it as a condition is not an actual
248    problem; however, it is a potential problem, since a later change in
249    export law could make the requirement nontrivial and thus render the
250    software nonfree.
251    </p>
252    
253    <p>
254    Most free software licenses are based on copyright, and there are limits
255    on what kinds of requirements can be imposed through copyright.  If a
256    copyright-based license respects freedom in the ways described above, it
257    is unlikely to have some other sort of problem that we never anticipated
258    (though this does happen occasionally).  However, some free software
259    licenses are based on contracts, and contracts can impose a much larger
260    range of possible restrictions.  That means there are many possible ways
261    such a license could be unacceptably restrictive and nonfree.
262    </p>
263    
264  <p>  <p>
265  Thus, you may have paid money to get copies of free software, or you  We can't possibly list all the ways that might happen.  If a
266  may have obtained copies at no charge.  But regardless of how you got  contract-based license restricts the user in an unusual way that
267  your copies, you always have the freedom to copy and change the  copyright-based licenses cannot, and which isn't mentioned here as
268  software, even to <a href="/philosophy/selling.html">sell copies</a>.</p>  legitimate, we will have to think about it, and we will probably conclude
269  <p>  it is nonfree.
270  ``Free software'' does not mean ``non-commercial''.  A free program  </p>
271  must be available for commercial use, commercial development, and  
272  commercial distribution.  Commercial development of free software is  <p>
273  no longer unusual; such free commercial software is very important.</p>  When talking about free software, it is best to avoid using terms
274  <p>  like &ldquo;give away&rdquo; or &ldquo;for free,&rdquo; because those terms imply that
275  Rules about how to package a modified version are acceptable, if they  the issue is about price, not freedom.  Some common terms such
276  don't effectively block your freedom to release modified versions.  as &ldquo;piracy&rdquo; embody opinions we hope you won't endorse.  See
277  Rules that ``if you make the program available in this way, you must  <a href="/philosophy/words-to-avoid.html">Confusing Words and Phrases that
278  make it available in that way also'' can be acceptable too, on the  are Worth Avoiding</a> for a discussion of these terms.  We also have
279  same condition.  (Note that such a rule still leaves you the choice of  a list of proper <a href="/philosophy/fs-translations.html">translations of
280  whether to publish the program or not.)  It is also acceptable for the  &ldquo;free software&rdquo;</a> into various languages.
281  license to require that, if you have distributed a modified version  </p>
282  and a previous developer asks for a copy of it, you must send one.</p>  
 <p>  
 In the GNU project, we use <a href="/copyleft/copyleft.html">``copyleft''</a>  
 to protect these freedoms legally for everyone.  But  
 <a href="/philosophy/categories.html#Non-CopyleftedFreeSoftware">non-copylefted  
 free software</a> also exists.  We believe there are  
 important reasons why <a href="/philosophy/pragmatic.html"> it is  
 better to use copyleft</a>, but if your program is non-copylefted free  
 software, we can still use it.</p>  
 <p>  
 See <a href="/philosophy/categories.html">Categories of Free Software</a>  
 for a description of how ``free software,'' ``copylefted software'' and  
 other categories of software relate to each other.</p>  
 <p>  
 Sometimes government <a id="exportcontrol">export control  
 regulations</a> and trade sanctions can constrain your freedom to  
 distribute copies of programs internationally.  Software developers do  
 not have the power to eliminate or override these restrictions, but  
 what they can and must do is refuse to impose them as conditions of  
 use of the program.  In this way, the restrictions will not affect  
 activities and people outside the jurisdictions of these governments.</p>  
 <p>  
 Most free software licenses are based on copyright, and there are  
 limits on what kinds of requirements can be imposed through copyright.  
 If a copyright-based license respects freedom in the ways described  
 above, it is unlikely to have some other sort of problem that we never  
 anticipated (though this does happen occasionally).  However, some  
 free software licenses are based on contracts, and contracts can  
 impose a much larger range of possible restrictions.  That means there  
 are many possible ways such a license could be unacceptably  
 restrictive and non-free.</p>  
 <p>  
 We can't possibly list all the possible contract restrictions that  
 would be unacceptable.  If a contract-based license restricts the user  
 in an unusual way that copyright-based licenses cannot, and which  
 isn't mentioned here as legitimate, we will have to think about it,  
 and we will probably decide it is non-free.</p>  
 <p>  
 When talking about free software, it is best to avoid using terms like  
 ``give away'' or ``for free'', because those terms imply that the  
 issue is about price, not freedom.  Some common terms such as  
 ``piracy'' embody opinions we hope you won't endorse.  See  
 <a href="/philosophy/words-to-avoid.html">Confusing Words and Phrases  
 that are Worth Avoiding</a> for a discussion of these terms.  
 We also have a list of <a href="/philosophy/fs-translations.html">translations  
 of "free software"</a> into various languages.</p>  
283  <p>  <p>
284  Finally, note that criteria such as those stated in this free software  Finally, note that criteria such as those stated in this free software
285  definition require careful thought for their interpretation.  To  definition require careful thought for their interpretation.  To decide
286  decide whether a specific software license qualifies as a free  whether a specific software license qualifies as a free software license,
287  software license, we judge it based on these criteria to determine  we judge it based on these criteria to determine whether it fits their
288  whether it fits their spirit as well as the precise words.  If a  spirit as well as the precise words.  If a license includes unconscionable
289  license includes unconscionable restrictions, we reject it, even if we  restrictions, we reject it, even if we did not anticipate the issue
290  did not anticipate the issue in these criteria.  Sometimes a license  in these criteria.  Sometimes a license requirement raises an issue
291  requirement raises an issue that calls for extensive thought,  that calls for extensive thought, including discussions with a lawyer,
292  including discussions with a lawyer, before we can decide if the  before we can decide if the requirement is acceptable.  When we reach
293  requirement is acceptable.  When we reach a conclusion about a new  a conclusion about a new issue, we often update these criteria to make
294  issue, we often update these criteria to make it easier to see why  it easier to see why certain licenses do or don't qualify.
 certain licenses do or don't qualify.</p>  
 <p>  
 If you are interested in whether a specific license qualifies as a  
 free software license, see our <a href="/licenses/license-list.html">list  
 of licenses</a>.  If the  
 license you are concerned with is not listed there, you can ask us  
 about it by sending us email  
 at <a href="mailto:licensing@gnu.org">&lt;licensing@gnu.org&gt;</a>.</p>  
   
 <hr />  
   
 <p>  
 Another group has started using the term "open source" to mean  
 something close (but not identical) to "free software".  We prefer the  
 term "free software" because, once you have heard it refers to freedom  
 rather than price, <a href="free-software-for-freedom.html">it calls  
 to mind freedom</a>.</p>  
   
 <hr />  
 <h4><a href="/philosophy/philosophy.html">Other Texts to Read</a></h4>  
   
   
 <!-- All pages on the GNU web server should have the section about    -->  
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 <p><a id="translations"></a>  
 <b>Translations of this page</b>:<br />  
   
 <!-- Please keep this list alphabetical, and in the original -->  
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295  </p>  </p>
 </div>  
296    
 <div class="copyright">  
297  <p>  <p>
298  Return to the <a href="/home.html">GNU Project home page</a>.  If you are interested in whether a specific license qualifies as a free
299    software license, see our <a href="/licenses/license-list.html">list
300    of licenses</a>.  If the license you are concerned with is not
301    listed there, you can ask us about it by sending us email at
302    <a href="mailto:licensing@gnu.org">&lt;licensing@gnu.org&gt;</a>.
303    </p>
304    
305    <p>
306    If you are contemplating writing a new license, please contact the
307    Free Software Foundation first by writing to that address. The
308    proliferation of different free software licenses means increased work
309    for users in understanding the licenses; we may be able to help you
310    find an existing free software license that meets your needs.
311  </p>  </p>
312    
313  <p>  <p>
314  Please send FSF &amp; GNU inquiries to  If that isn't possible, if you really need a new license, with our
315  <a href="mailto:gnu@gnu.org"><em>gnu@gnu.org</em></a>.  help you can ensure that the license really is a free software license
316  There are also <a href="/home.html#ContactInfo">other ways to contact</a>  and avoid various practical problems.
 the FSF.  
 <br />  
 Please send broken links and other corrections (or suggestions) to  
 <a href="mailto:webmasters@gnu.org"><em>webmasters@gnu.org</em></a>.  
317  </p>  </p>
318    
319    <h3 id="beyond-software">Beyond Software</h3>
320    
321  <p>  <p>
322  Please see the  <a href="/philosophy/free-doc.html">Software manuals must be free</a>,
323  <a href="/server/standards/README.translations.html">Translations  for the same reasons that software must be free, and because the
324  README</a> for information on coordinating and submitting  manuals are in effect part of the software.
 translations of this article.  
325  </p>  </p>
326    
327  <p>  <p>
328  Copyright (C) 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003, Free  The same arguments also make sense for other kinds of works of
329  Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  practical use &mdash; that is to say, works that embody useful knowledge,
330  02111,  USA  such as educational works and reference
331  <br />  works.  <a href="http://wikipedia.org">Wikipedia</a> is the best-known
332  Verbatim copying and distribution of this entire article is  example.
 permitted in any medium without royalty provided this notice is  
 preserved.  
333  </p>  </p>
334    
335  <p>  <p>
336  Updated:  Any kind of work <em>can</em> be free, and the definition of free software
337    has been extended to a definition of <a href="http://freedomdefined.org/">
338    free cultural works</a> applicable to any kind of works.
339    </p>
340    
341    <h3 id="open-source">Open Source?</h3>
342    
343    <p>
344    Another group has started using the term &ldquo;open source&rdquo; to mean
345    something close (but not identical) to &ldquo;free software&rdquo;.  We
346    prefer the term &ldquo;free software&rdquo; because, once you have heard that
347    it refers to freedom rather than price, it calls to mind freedom.  The
348    word &ldquo;open&rdquo; <a href="/philosophy/open-source-misses-the-point.html">
349    never refers to freedom</a>.
350    </p>
351    
352    <h3 id="History">History</h3>
353    
354    <p>From time to time we revise this Free Software Definition.  Here is
355    the list of substantive changes, along with links to show exactly what
356    was changed.</p>
357    
358    <ul>
359    
360    <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
361    1.122</a>: An export control requirement is a real problem if the
362    requirement is nontrivial; otherwise it is only a potential problem.</li>
363    
364    <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
365    1.118</a>: Clarification: the issue is limits on your right to modify,
366    not on what modifications you have made.  And modifications are not limited
367    to &ldquo;improvements&rdquo;</li>
368    
369    <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
370    1.111</a>: Clarify 1.77 by saying that only
371    retroactive <em>restrictions</em> are unacceptable.  The copyright
372    holders can always grant additional <em>permission</em> for use of the
373    work by releasing the work in another way in parallel.</li>
374    
375    <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
376    1.105</a>: Reflect, in the brief statement of freedom 1, the point
377    (already stated in version 1.80) that it includes really using your modified
378    version for your computing.</li>
379    
380    <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
381    1.92</a>: Clarify that obfuscated code does not qualify as source code.</li>
382    
383    <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
384    1.90</a>: Clarify that freedom 3 means the right to distribute copies
385    of your own modified or improved version, not a right to participate
386    in someone else's development project.</li>
387    
388    <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
389    1.89</a>: Freedom 3 includes the right to release modified versions as
390    free software.</li>
391    
392    <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
393    1.80</a>: Freedom 1 must be practical, not just theoretical;
394    i.e., no tivoization.</li>
395    
396    <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
397    1.77</a>: Clarify that all retroactive changes to the license are
398    unacceptable, even if it's not described as a complete
399    replacement.</li>
400    
401    <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
402    1.74</a>: Four clarifications of points not explicit enough, or stated
403    in some places but not reflected everywhere:
404    <ul>
405    <li>"Improvements" does not mean the license can
406    substantively limit what kinds of modified versions you can release.
407    Freedom 3 includes distributing modified versions, not just changes.</li>
408    <li>The right to merge in existing modules
409    refers to those that are suitably licensed.</li>
410    <li>Explicitly state the conclusion of the point about export controls.</li>
411    <li>Imposing a license change constitutes revoking the old license.</li>
412    </ul>
413    </li>
414    
415    <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
416    1.57</a>: Add &quot;Beyond Software&quot; section.</li>
417    
418    <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
419    1.46</a>: Clarify whose purpose is significant in the freedom to run
420    the program for any purpose.</li>
421    
422    <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
423    1.41</a>: Clarify wording about contract-based licenses.</li>
424    
425    <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
426    1.40</a>: Explain that a free license must allow to you use other
427    available free software to create your modifications.</li>
428    
429    <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
430    1.39</a>: Note that it is acceptable for a license to require you to
431    provide source for versions of the software you put into public
432    use.</li>
433    
434    <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
435    1.31</a>: Note that it is acceptable for a license to require you to
436    identify yourself as the author of modifications.  Other minor
437    clarifications throughout the text.</li>
438    
439    <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
440    1.23</a>: Address potential problems related to contract-based
441    licenses.</li>
442    
443    <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
444    1.16</a>: Explain why distribution of binaries is important.</li>
445    
446    <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
447    1.11</a>: Note that a free license may require you to send a copy of
448    versions you distribute to the author.</li>
449    
450    </ul>
451    
452    <p>There are gaps in the version numbers shown above because there are
453    other changes in this page that do not affect the definition or its
454    interpretations.  For instance, the list does not include changes in
455    asides, formatting, spelling, punctuation, or other parts of the page.
456    You can review the complete list of changes to the page through
457    the <a href="http://web.cvs.savannah.gnu.org/viewvc/www/philosophy/free-sw.html?root=www&amp;view=log">cvsweb
458    interface</a>.</p>
459    
460    
461    </div><!-- for id="content", starts in the include above -->
462    <!--#include virtual="/server/footer.html" -->
463    <div id="footer">
464    
465    <p>Please send general FSF &amp; GNU inquiries to
466    <a href="mailto:gnu@gnu.org">&lt;gnu@gnu.org&gt;</a>.
467    There are also <a href="/contact/">other ways to contact</a>
468    the FSF.  Broken links and other corrections or suggestions can be sent
469    to <a href="mailto:webmasters@gnu.org">&lt;webmasters@gnu.org&gt;</a>.</p>
470    
471    <p><!-- TRANSLATORS: Ignore the original text in this paragraph,
472            replace it with the translation of these two:
473    
474            We work hard and do our best to provide accurate, good quality
475            translations.  However, we are not exempt from imperfection.
476            Please send your comments and general suggestions in this regard
477            to <a href="mailto:web-translators@gnu.org">
478            &lt;web-translators@gnu.org&gt;</a>.</p>
479    
480            <p>For information on coordinating and submitting translations of
481            our web pages, see <a
482            href="/server/standards/README.translations.html">Translations
483            README</a>. -->
484    Please see the <a
485    href="/server/standards/README.translations.html">Translations
486    README</a> for information on coordinating and submitting translations
487    of this article.</p>
488    
489    <!-- Regarding copyright, in general, standalone pages (as opposed to
490         files generated as part of manuals) on the GNU web server should
491         be under CC BY-ND 3.0 US.  Please do NOT change or remove this
492         without talking with the webmasters or licensing team first.
493         Please make sure the copyright date is consistent with the
494         document.  For web pages, it is ok to list just the latest year the
495         document was modified, or published.
496        
497         If you wish to list earlier years, that is ok too.
498         Either "2001, 2002, 2003" or "2001-2003" are ok for specifying
499         years, as long as each year in the range is in fact a copyrightable
500         year, i.e., a year in which the document was published (including
501         being publicly visible on the web or in a revision control system).
502        
503         There is more detail about copyright years in the GNU Maintainers
504         Information document, www.gnu.org/prep/maintain. -->
505    
506    <p>Copyright &copy; 1996-2002, 2004-2007, 2009, 2010, 2012, 2013
507    Free Software Foundation, Inc.</p>
508    
509    <p>This page is licensed under a <a rel="license"
510    href="http://creativecommons.org/licenses/by-nd/3.0/us/">Creative
511    Commons Attribution-NoDerivs 3.0 United States License</a>.</p>
512    
513    <!--#include virtual="/server/bottom-notes.html" -->
514    
515    <p>Updated:
516  <!-- timestamp start -->  <!-- timestamp start -->
517  $Date$ $Author$  $Date$
518  <!-- timestamp end -->  <!-- timestamp end -->
519  </p>  </p>
520  </div>  </div>
521    </div>
522  </body>  </body>
523  </html>  </html>

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