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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>
18    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>
25    </blockquote>
26    
27  <p>  <p>
28  <a href="/graphics/philosophicalgnu.html"><img src="/graphics/philosophical-gnu-sm.jpg" alt=" [image of a Philosophical Gnu] " width="160" height="200" /></a>  &ldquo;Free software&rdquo; means software that respects users'
29    freedom and community.  Roughly, <b>the users have the freedom to run,
30    copy, distribute, study, change and improve the software</b>.
31  </p>  </p>
32    
33  <p>  <p>
34  We maintain this free software definition to show clearly what must be  Thus, &ldquo;free software&rdquo; is a matter of liberty, not price.
35  true about a particular software program for it to be considered  To understand the concept, you should think of &ldquo;free&rdquo; as
36  free software.</p>  in &ldquo;free speech,&rdquo; not as in &ldquo;free beer&rdquo;.
37    </p>
38    
39  <p>  <p>
40  ``Free software'' is a matter of liberty, not price.  To understand the  With these freedoms, the users (both individually and collectively)
41  concept, you should think of ``free'' as in ``free speech,'' not as in  control the program and what it does for them.  When users don't
42  ``free beer.''</p>  control the program, the program controls the users.  The developer
43    controls the program, and through it exercises power over the users.
44    Therefore, a &ldquo;nonfree&rdquo; or &ldquo;proprietary&rdquo; program
45    is <a href="/philosophy/free-software-even-more-important.html"> an
46    instrument of unjust power</a>.
47    </p>
48    
49  <p>  <p>
50  Free software is a matter of the users' freedom to run, copy,  A program is free software if the program's users have the
51  distribute, study, change and improve the software.  More precisely,  four essential freedoms:
52  it refers to four kinds of freedom, for the users of the software:</p>  </p>
53    
54  <ul>  <ul>
55    <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>
56    <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
57        (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
58          code is a precondition for this.
59      </li>
60    <li>The freedom to redistribute copies so you can help your neighbor    <li>The freedom to redistribute copies so you can help your neighbor
61        (freedom 2).</li>        (freedom 2).
62    <li>The freedom to improve the program, and release your improvements    </li>
63       to the public, so that the whole community benefits    <li>The freedom to distribute copies of your modified versions
64        (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
65          community a chance to benefit from your changes.
66          Access to the source code is a precondition for this.
67      </li>
68  </ul>  </ul>
69    
70  <p>  <p>
71  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
72  Thus, you should be free to redistribute copies, either with or  freedoms.  Otherwise, it is nonfree.  While we can distinguish various
73  without modifications, either gratis or charging a fee for  nonfree distribution schemes in terms of how far they fall short of
74  distribution, to <a href="#exportcontrol">anyone anywhere</a>.  Being  being free, we consider them all equally unethical.</p>
75  free to do these things means (among other things) that you do not  
76  have to ask or pay for permission.</p>  <p>The rest of this page clarifies certain points about what makes
77    specific freedoms adequate or not.</p>
78    
79    <p>Freedom to distribute (freedoms 2 and 3) means you are free to
80    redistribute copies, either with or without modifications, either
81    gratis or charging a fee for distribution, to
82    <a href="#exportcontrol">anyone anywhere</a>.  Being free to do these
83    things means (among other things) that you do not have to ask or pay
84    for permission to do so.
85    </p>
86    
87  <p>  <p>
88  You should also have the freedom to make modifications and use them  You should also have the freedom to make modifications and use them
89  privately in your own work or play, without even mentioning that they  privately in your own work or play, without even mentioning that they
90  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
91  notify anyone in particular, or in any particular way.</p>  notify anyone in particular, or in any particular way.
92    </p>
93    
94  <p>  <p>
95  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
96  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
97  of overall job, and without being required to communicate subsequently  overall job and purpose, without being required to communicate about it
98  with the developer or any other specific entity.</p>  with the developer or any other specific entity.  In this freedom, it is
99    the <em>user's</em> purpose that matters, not the <em>developer's</em>
100    purpose; you as a user are free to run the program for your purposes,
101    and if you distribute it to someone else, she is then free to run it
102    for her purposes, but you are not entitled to impose your purposes on her.
103    </p>
104    
105  <p>  <p>
106  The freedom to redistribute copies must include binary or executable  The freedom to redistribute copies must include binary or executable
107  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
108  unmodified versions.  (Distributing programs in runnable form is  unmodified versions.  (Distributing programs in runnable form is necessary
109  necessary for conveniently installable free operating systems.)  It is  for conveniently installable free operating systems.)  It is OK if there
110  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
111  certain program (since some languages don't support that feature), but  (since some languages don't support that feature), but you must have the
112  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
113  or develop a way to make them.</p>  make them.
114  <p>  </p>
115  In order for the freedoms to make changes, and to publish improved  
116  versions, to be meaningful, you must have access to the source code of  <p>
117  the program.  Therefore, accessibility of source code is a necessary  In order for freedoms 1 and 3 (the freedom to make changes and the
118  condition for free software.</p>  freedom to publish the changed versions) to be meaningful, you must have
119  <p>  access to the source code of the program.  Therefore, accessibility of
120  In order for these freedoms to be real, they must be irrevocable as  source code is a necessary condition for free software.  Obfuscated
121  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
122  power to revoke the license, without your doing anything to give  as source code.
123  cause, the software is not free.</p>  </p>
124    
125    <p>
126    Freedom 1 includes the freedom to use your changed version in place of
127    the original.  If the program is delivered in a product designed to
128    run someone else's modified versions but refuse to run yours &mdash; a
129    practice known as &ldquo;tivoization&rdquo; or &ldquo;lockdown&rdquo;,
130    or (in its practitioners' perverse terminology) as &ldquo;secure
131    boot&rdquo; &mdash; freedom 1 becomes a theoretical fiction rather
132    than a practical freedom.  This is not sufficient.  In other words,
133    these binaries are not free software even if the source code they are
134    compiled from is free.
135    </p>
136    
137    <p>
138    One important way to modify a program is by merging in available free
139    subroutines and modules.  If the program's license says that you
140    cannot merge in a suitably licensed existing module &mdash; for instance, if it
141    requires you to be the copyright holder of any code you add &mdash; then the
142    license is too restrictive to qualify as free.
143    </p>
144    
145    <p>
146    Freedom 3 includes the freedom to release your modified versions
147    as free software.  A free license may also permit other ways of
148    releasing them; in other words, it does not have to be
149    a <a href="/copyleft/copyleft.html">copyleft</a> license.  However, a
150    license that requires modified versions to be nonfree does not qualify
151    as a free license.
152    </p>
153    
154    <p>
155    In order for these freedoms to be real, they must be permanent and
156    irrevocable as long as you do nothing wrong; if the developer of the
157    software has the power to revoke the license, or retroactively add
158    restrictions to its terms, without your doing anything wrong to give
159    cause, the software is not free.
160    </p>
161    
162  <p>  <p>
163  However, certain kinds of rules about the manner of distributing free  However, certain kinds of rules about the manner of distributing free
164  software are acceptable, when they don't conflict with the central  software are acceptable, when they don't conflict with the central
165  freedoms.  For example, copyleft (very simply stated) is the rule that  freedoms.  For example, copyleft (very simply stated) is the rule that
166  when redistributing the program, you cannot add restrictions to deny  when redistributing the program, you cannot add restrictions to deny
167  other people the central freedoms.  This rule does not conflict with  other people the central freedoms.  This rule does not conflict with
168  the central freedoms; rather it protects them.</p>  the central freedoms; rather it protects them.
169    </p>
170    
171  <p>  <p>
172  You may have paid money to get copies of free software, or you  &ldquo;Free software&rdquo; does not mean &ldquo;noncommercial&rdquo;.  A free
173  may have obtained copies at no charge.  But regardless of how you got  program must be available for commercial use, commercial development,
174  your copies, you always have the freedom to copy and change the  and commercial distribution.  Commercial development of free software
175  software, even to <a href="/philosophy/selling.html">sell copies</a>.</p>  is no longer unusual; such free commercial software is very important.
176  <p>  You may have paid money to get copies of free software, or you may have
177  ``Free software'' does not mean ``non-commercial''.  A free program  obtained copies at no charge.  But regardless of how you got your copies,
178  must be available for commercial use, commercial development, and  you always have the freedom to copy and change the software, even to
179  commercial distribution.  Commercial development of free software is  <a href="/philosophy/selling.html">sell copies</a>.
180  no longer unusual; such free commercial software is very important.</p>  </p>
181  <p>  
 Rules about how to package a modified version are acceptable, if they  
 don't substantively block your freedom to release modified versions.  
 Rules that ``if you make the program available in this way, you must  
 make it available in that way also'' can be acceptable too, on the  
 same condition.  (Note that such a rule still leaves you the choice of  
 whether to publish the program or not.)  It is also acceptable for the  
 license to require that, if you have distributed a modified version  
 and a previous developer asks for a copy of it, you must send one,  
 or that you identify yourself on your modifications.</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>  
182  <p>  <p>
183  Finally, note that criteria such as those stated in this free software  Whether a change constitutes an improvement is a subjective matter.
184  definition require careful thought for their interpretation.  To  If your right to modify a program is limited, in substance, to changes that
185  decide whether a specific software license qualifies as a free  someone else considers an improvement, that program is not free.
 software license, we judge it based on these criteria to determine  
 whether it fits their spirit as well as the precise words.  If a  
 license includes unconscionable restrictions, we reject it, even if we  
 did not anticipate the issue in these criteria.  Sometimes a license  
 requirement raises an issue that calls for extensive thought,  
 including discussions with a lawyer, before we can decide if the  
 requirement is acceptable.  When we reach a conclusion about a new  
 issue, we often update these criteria to make it easier to see why  
 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> <p>  
 If you are contemplating writing a new license, please contact the FSF  
 by writing to that address. The proliferation of different free  
 software licenses means increased work for users in understanding the  
 licenses; we may be able to help you find an existing Free Software  
 license that meets your needs.  
186  </p>  </p>
187    
188  <p>  <p>
189  If that isn't possible, if you really need a new license, with our  However, rules about how to package a modified version are acceptable,
190  help you can ensure that the license really is a Free Software license  if they don't substantively limit your freedom to release modified
191  and avoid various practical problems.  versions, or your freedom to make and use modified versions privately.
192    Thus, it is acceptable for the license to require that you change the
193    name of the modified version, remove a logo, or identify your
194    modifications as yours.  As long as these requirements are not so
195    burdensome that they effectively hamper you from releasing your
196    changes, they are acceptable; you're already making other changes to
197    the program, so you won't have trouble making a few more.
198  </p>  </p>
 <hr />  
199    
200  <p>  <p>
201  Another group has started using the term "open source" to mean  Rules that &ldquo;if you make your version available in this way, you
202  something close (but not identical) to "free software".  We prefer the  must make it available in that way also&rdquo; can be acceptable too,
203  term "free software" because, once you have heard it refers to freedom  on the same condition.  An example of such an acceptable rule is one
204  rather than price, <a href="free-software-for-freedom.html">it calls  saying that if you have distributed a
205  to mind freedom</a>.  The word "open" never does that.</p>  modified version and a previous developer asks for a copy of it, you
206    must send one.  (Note that such a rule still leaves you the choice of
207  <hr />  whether to distribute your version at all.)  Rules that require release
208  <h4><a href="/philosophy/philosophy.html">Other Texts to Read</a></h4>  of source code to the users for versions that you put into public use
209    are also acceptable.
   
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 [  
   <a href="/philosophy/free-sw.ca.html">Catal&#x00e0;</a>       <!-- Catalan -->  
   
 <!-- Chinese (Simplified) -->  
 | <a href="/philosophy/free-sw.cn.html">&#x7b80;&#x4f53;&#x4e2d;&#x6587;</a>  
   
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 | <a href="/philosophy/free-sw.html">English</a>  
 | <a href="/philosophy/free-sw.es.html">Espa&#x00f1;ol</a>      <!-- Spanish -->  
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 | <a href="/philosophy/free-sw.gl.html">Galego</a>      <!-- Galician -->  
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 | <a href="/philosophy/free-sw.ja.html">&#x65e5;&#x672c;&#x8a9e;</a>    <!-- Japanese -->  
 | <a href="/philosophy/free-sw.ko.html">&#xd55c;&#xad6d;&#xc5b4;</a>    <!-- Korean -->  
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 | <a href="/philosophy/free-sw.ro.html">Rom&#x00e2;n&#x00e3;</a>        <!-- Romanian -->  
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 | <a href="/philosophy/free-sw.sl.html">Slovinsko</a>   <!--- Slovenian -->  
 | <a href="/philosophy/free-sw.tr.html">T&#x00fc;rk&#x00e7;e</a>        <!-- Turkish -->  
 ]  
210  </p>  </p>
 </div>  
211    
 <div class="copyright">  
212  <p>  <p>
213  Return to the <a href="/home.html">GNU Project home page</a>.  A special issue arises when a license requires changing the name by
214    which the program will be invoked from other programs.  That
215    effectively hampers you from releasing your changed version so that it
216    can replace the original when invoked by those other programs.  This
217    sort of requirement is acceptable only if there's a suitable aliasing
218    facility that allows you to specify the original program's name as an
219    alias for the modified version.</p>
220    
221    <p>
222    In the GNU project, we use
223    <a href="/copyleft/copyleft.html">copyleft</a>
224    to protect these freedoms legally for everyone.  But
225    <a href="/philosophy/categories.html#Non-CopyleftedFreeSoftware">noncopylefted
226    free software</a> also exists.  We believe there are important reasons why
227    <a href="/philosophy/pragmatic.html">it is better to use copyleft</a>,
228    but if your program is noncopylefted free software, it is still basically
229    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.)
230  </p>  </p>
231    
232  <p>  <p>
233  Please send FSF &amp; GNU inquiries to  Sometimes government <a id="exportcontrol">export control regulations</a>
234  <a href="mailto:gnu@gnu.org"><em>gnu@gnu.org</em></a>.  and trade sanctions can constrain your freedom to distribute copies of
235  There are also <a href="/home.html#ContactInfo">other ways to contact</a>  programs internationally.  Software developers do not have the power to
236  the FSF.  eliminate or override these restrictions, but what they can and must do
237  <br />  is refuse to impose them as conditions of use of the program.  In this
238  Please send broken links and other corrections (or suggestions) to  way, the restrictions will not affect activities and people outside the
239  <a href="mailto:webmasters@gnu.org"><em>webmasters@gnu.org</em></a>.  jurisdictions of these governments.  Thus, free software licenses
240    must not require obedience to any nontrivial export regulations as a
241    condition of exercising any of the essential freedoms.
242  </p>  </p>
243    
244  <p>  <p>
245  Please see the  Merely mentioning the existence of export regulations, without making
246  <a href="/server/standards/README.translations.html">Translations  them a condition of the license itself, is acceptable since it does
247  README</a> for information on coordinating and submitting  not restrict users.  If an export regulation is actually trivial for
248  translations of this article.  free software, then requiring it as a condition is not an actual
249    problem; however, it is a potential problem, since a later change in
250    export law could make the requirement nontrivial and thus render the
251    software nonfree.
252  </p>  </p>
253    
254  <p>  <p>
255  Copyright (C) 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004 Free  Most free software licenses are based on copyright, and there are limits
256  Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  on what kinds of requirements can be imposed through copyright.  If a
257  02111,  USA  copyright-based license respects freedom in the ways described above, it
258  <br />  is unlikely to have some other sort of problem that we never anticipated
259  Verbatim copying and distribution of this entire article is  (though this does happen occasionally).  However, some free software
260  permitted in any medium without royalty provided this notice is  licenses are based on contracts, and contracts can impose a much larger
261  preserved.  range of possible restrictions.  That means there are many possible ways
262    such a license could be unacceptably restrictive and nonfree.
263  </p>  </p>
264    
265  <p>  <p>
266  Updated:  We can't possibly list all the ways that might happen.  If a
267    contract-based license restricts the user in an unusual way that
268    copyright-based licenses cannot, and which isn't mentioned here as
269    legitimate, we will have to think about it, and we will probably conclude
270    it is nonfree.
271    </p>
272    
273    <p>
274    When talking about free software, it is best to avoid using terms
275    like &ldquo;give away&rdquo; or &ldquo;for free,&rdquo; because those terms imply that
276    the issue is about price, not freedom.  Some common terms such
277    as &ldquo;piracy&rdquo; embody opinions we hope you won't endorse.  See
278    <a href="/philosophy/words-to-avoid.html">Confusing Words and Phrases that
279    are Worth Avoiding</a> for a discussion of these terms.  We also have
280    a list of proper <a href="/philosophy/fs-translations.html">translations of
281    &ldquo;free software&rdquo;</a> into various languages.
282    </p>
283    
284    <p>
285    Finally, note that criteria such as those stated in this free software
286    definition require careful thought for their interpretation.  To decide
287    whether a specific software license qualifies as a free software license,
288    we judge it based on these criteria to determine whether it fits their
289    spirit as well as the precise words.  If a license includes unconscionable
290    restrictions, we reject it, even if we did not anticipate the issue
291    in these criteria.  Sometimes a license requirement raises an issue
292    that calls for extensive thought, including discussions with a lawyer,
293    before we can decide if the requirement is acceptable.  When we reach
294    a conclusion about a new issue, we often update these criteria to make
295    it easier to see why certain licenses do or don't qualify.
296    </p>
297    
298    <p>
299    If you are interested in whether a specific license qualifies as a free
300    software license, see our <a href="/licenses/license-list.html">list
301    of licenses</a>.  If the license you are concerned with is not
302    listed there, you can ask us about it by sending us email at
303    <a href="mailto:licensing@gnu.org">&lt;licensing@gnu.org&gt;</a>.
304    </p>
305    
306    <p>
307    If you are contemplating writing a new license, please contact the
308    Free Software Foundation first by writing to that address. The
309    proliferation of different free software licenses means increased work
310    for users in understanding the licenses; we may be able to help you
311    find an existing free software license that meets your needs.
312    </p>
313    
314    <p>
315    If that isn't possible, if you really need a new license, with our
316    help you can ensure that the license really is a free software license
317    and avoid various practical problems.
318    </p>
319    
320    <h3 id="beyond-software">Beyond Software</h3>
321    
322    <p>
323    <a href="/philosophy/free-doc.html">Software manuals must be free</a>,
324    for the same reasons that software must be free, and because the
325    manuals are in effect part of the software.
326    </p>
327    
328    <p>
329    The same arguments also make sense for other kinds of works of
330    practical use &mdash; that is to say, works that embody useful knowledge,
331    such as educational works and reference
332    works.  <a href="http://wikipedia.org">Wikipedia</a> is the best-known
333    example.
334    </p>
335    
336    <p>
337    Any kind of work <em>can</em> be free, and the definition of free software
338    has been extended to a definition of <a href="http://freedomdefined.org/">
339    free cultural works</a> applicable to any kind of works.
340    </p>
341    
342    <h3 id="open-source">Open Source?</h3>
343    
344    <p>
345    Another group has started using the term &ldquo;open source&rdquo; to mean
346    something close (but not identical) to &ldquo;free software&rdquo;.  We
347    prefer the term &ldquo;free software&rdquo; because, once you have heard that
348    it refers to freedom rather than price, it calls to mind freedom.  The
349    word &ldquo;open&rdquo; <a href="/philosophy/open-source-misses-the-point.html">
350    never refers to freedom</a>.
351    </p>
352    
353    <h3 id="History">History</h3>
354    
355    <p>From time to time we revise this Free Software Definition.  Here is
356    the list of substantive changes, along with links to show exactly what
357    was changed.</p>
358    
359    <ul>
360    
361    <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
362    1.122</a>: An export control requirement is a real problem if the
363    requirement is nontrivial; otherwise it is only a potential problem.</li>
364    
365    <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
366    1.118</a>: Clarification: the issue is limits on your right to modify,
367    not on what modifications you have made.  And modifications are not limited
368    to &ldquo;improvements&rdquo;</li>
369    
370    <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
371    1.111</a>: Clarify 1.77 by saying that only
372    retroactive <em>restrictions</em> are unacceptable.  The copyright
373    holders can always grant additional <em>permission</em> for use of the
374    work by releasing the work in another way in parallel.</li>
375    
376    <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
377    1.105</a>: Reflect, in the brief statement of freedom 1, the point
378    (already stated in version 1.80) that it includes really using your modified
379    version for your computing.</li>
380    
381    <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
382    1.92</a>: Clarify that obfuscated code does not qualify as source code.</li>
383    
384    <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
385    1.90</a>: Clarify that freedom 3 means the right to distribute copies
386    of your own modified or improved version, not a right to participate
387    in someone else's development project.</li>
388    
389    <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
390    1.89</a>: Freedom 3 includes the right to release modified versions as
391    free software.</li>
392    
393    <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
394    1.80</a>: Freedom 1 must be practical, not just theoretical;
395    i.e., no tivoization.</li>
396    
397    <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
398    1.77</a>: Clarify that all retroactive changes to the license are
399    unacceptable, even if it's not described as a complete
400    replacement.</li>
401    
402    <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
403    1.74</a>: Four clarifications of points not explicit enough, or stated
404    in some places but not reflected everywhere:
405    <ul>
406    <li>"Improvements" does not mean the license can
407    substantively limit what kinds of modified versions you can release.
408    Freedom 3 includes distributing modified versions, not just changes.</li>
409    <li>The right to merge in existing modules
410    refers to those that are suitably licensed.</li>
411    <li>Explicitly state the conclusion of the point about export controls.</li>
412    <li>Imposing a license change constitutes revoking the old license.</li>
413    </ul>
414    </li>
415    
416    <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
417    1.57</a>: Add &quot;Beyond Software&quot; section.</li>
418    
419    <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
420    1.46</a>: Clarify whose purpose is significant in the freedom to run
421    the program for any purpose.</li>
422    
423    <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
424    1.41</a>: Clarify wording about contract-based licenses.</li>
425    
426    <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
427    1.40</a>: Explain that a free license must allow to you use other
428    available free software to create your modifications.</li>
429    
430    <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
431    1.39</a>: Note that it is acceptable for a license to require you to
432    provide source for versions of the software you put into public
433    use.</li>
434    
435    <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
436    1.31</a>: Note that it is acceptable for a license to require you to
437    identify yourself as the author of modifications.  Other minor
438    clarifications throughout the text.</li>
439    
440    <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
441    1.23</a>: Address potential problems related to contract-based
442    licenses.</li>
443    
444    <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
445    1.16</a>: Explain why distribution of binaries is important.</li>
446    
447    <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
448    1.11</a>: Note that a free license may require you to send a copy of
449    versions you distribute to the author.</li>
450    
451    </ul>
452    
453    <p>There are gaps in the version numbers shown above because there are
454    other changes in this page that do not affect the definition or its
455    interpretations.  For instance, the list does not include changes in
456    asides, formatting, spelling, punctuation, or other parts of the page.
457    You can review the complete list of changes to the page through
458    the <a href="http://web.cvs.savannah.gnu.org/viewvc/www/philosophy/free-sw.html?root=www&amp;view=log">cvsweb
459    interface</a>.</p>
460    
461    
462    </div><!-- for id="content", starts in the include above -->
463    <!--#include virtual="/server/footer.html" -->
464    <div id="footer">
465    
466    <p>Please send general FSF &amp; GNU inquiries to
467    <a href="mailto:gnu@gnu.org">&lt;gnu@gnu.org&gt;</a>.
468    There are also <a href="/contact/">other ways to contact</a>
469    the FSF.  Broken links and other corrections or suggestions can be sent
470    to <a href="mailto:webmasters@gnu.org">&lt;webmasters@gnu.org&gt;</a>.</p>
471    
472    <p><!-- TRANSLATORS: Ignore the original text in this paragraph,
473            replace it with the translation of these two:
474    
475            We work hard and do our best to provide accurate, good quality
476            translations.  However, we are not exempt from imperfection.
477            Please send your comments and general suggestions in this regard
478            to <a href="mailto:web-translators@gnu.org">
479            &lt;web-translators@gnu.org&gt;</a>.</p>
480    
481            <p>For information on coordinating and submitting translations of
482            our web pages, see <a
483            href="/server/standards/README.translations.html">Translations
484            README</a>. -->
485    Please see the <a
486    href="/server/standards/README.translations.html">Translations
487    README</a> for information on coordinating and submitting translations
488    of this article.</p>
489    
490    <!-- Regarding copyright, in general, standalone pages (as opposed to
491         files generated as part of manuals) on the GNU web server should
492         be under CC BY-ND 3.0 US.  Please do NOT change or remove this
493         without talking with the webmasters or licensing team first.
494         Please make sure the copyright date is consistent with the
495         document.  For web pages, it is ok to list just the latest year the
496         document was modified, or published.
497        
498         If you wish to list earlier years, that is ok too.
499         Either "2001, 2002, 2003" or "2001-2003" are ok for specifying
500         years, as long as each year in the range is in fact a copyrightable
501         year, i.e., a year in which the document was published (including
502         being publicly visible on the web or in a revision control system).
503        
504         There is more detail about copyright years in the GNU Maintainers
505         Information document, www.gnu.org/prep/maintain. -->
506    
507    <p>Copyright &copy; 1996-2002, 2004-2007, 2009, 2010, 2012, 2013
508    Free Software Foundation, Inc.</p>
509    
510    <p>This page is licensed under a <a rel="license"
511    href="http://creativecommons.org/licenses/by-nd/3.0/us/">Creative
512    Commons Attribution-NoDerivs 3.0 United States License</a>.</p>
513    
514    <!--#include virtual="/server/bottom-notes.html" -->
515    
516    <p>Updated:
517  <!-- timestamp start -->  <!-- timestamp start -->
518  $Date$ $Author$  $Date$
519  <!-- timestamp end -->  <!-- timestamp end -->
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521  </div>  </div>
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