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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; this 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    In the GNU project, we use <a href="/copyleft/copyleft.html">
172    copyleft </a> to protect the four freedoms legally for everyone.  We
173    believe there are important reasons why
174    <a href="/philosophy/pragmatic.html">it is better to use
175    copyleft</a>.  However,
176    <a href="/philosophy/categories.html#Non-CopyleftedFreeSoftware">
177    noncopylefted free software</a> is ethical
178    too.  See <a href="/philosophy/categories.html">Categories of Free
179    Software</a> for a description of how &ldquo;free software,&rdquo;
180    &ldquo;copylefted software&rdquo; and other categories of software
181    relate to each other.
182    </p>
183    
184  <p>  <p>
185  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
186  may have obtained copies at no charge.  But regardless of how you got  program must be available for commercial use, commercial development,
187  your copies, you always have the freedom to copy and change the  and commercial distribution.  Commercial development of free software
188  software, even to <a href="/philosophy/selling.html">sell copies</a>.</p>  is no longer unusual; such free commercial software is very important.
189  <p>  You may have paid money to get copies of free software, or you may have
190  ``Free software'' does not mean ``non-commercial''.  A free program  obtained copies at no charge.  But regardless of how you got your copies,
191  must be available for commercial use, commercial development, and  you always have the freedom to copy and change the software, even to
192  commercial distribution.  Commercial development of free software is  <a href="/philosophy/selling.html">sell copies</a>.
193  no longer unusual; such free commercial software is very important.</p>  </p>
194  <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>  
195  <p>  <p>
196  Finally, note that criteria such as those stated in this free software  Whether a change constitutes an improvement is a subjective matter.
197  definition require careful thought for their interpretation.  To  If your right to modify a program is limited, in substance, to changes that
198  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.  
199  </p>  </p>
200    
201  <p>  <p>
202  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,
203  help you can ensure that the license really is a Free Software license  if they don't substantively limit your freedom to release modified
204  and avoid various practical problems.  versions, or your freedom to make and use modified versions privately.
205    Thus, it is acceptable for the license to require that you change the
206    name of the modified version, remove a logo, or identify your
207    modifications as yours.  As long as these requirements are not so
208    burdensome that they effectively hamper you from releasing your
209    changes, they are acceptable; you're already making other changes to
210    the program, so you won't have trouble making a few more.
211  </p>  </p>
 <hr />  
212    
213  <p>  <p>
214  Another group has started using the term "open source" to mean  Rules that &ldquo;if you make your version available in this way, you
215  something close (but not identical) to "free software".  We prefer the  must make it available in that way also&rdquo; can be acceptable too,
216  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
217  rather than price, <a href="free-software-for-freedom.html">it calls  saying that if you have distributed a
218  to mind freedom</a>.  The word "open" never does that.</p>  modified version and a previous developer asks for a copy of it, you
219    must send one.  (Note that such a rule still leaves you the choice of
220  <hr />  whether to distribute your version at all.)  Rules that require release
221  <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
222    are also acceptable.
   
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 ]  
223  </p>  </p>
 </div>  
224    
 <div class="copyright">  
225  <p>  <p>
226  Return to the <a href="/home.html">GNU Project home page</a>.  A special issue arises when a license requires changing the name by
227    which the program will be invoked from other programs.  That
228    effectively hampers you from releasing your changed version so that it
229    can replace the original when invoked by those other programs.  This
230    sort of requirement is acceptable only if there's a suitable aliasing
231    facility that allows you to specify the original program's name as an
232    alias for the modified version.</p>
233    
234    <p>
235    Sometimes government <a id="exportcontrol">export control regulations</a>
236    and trade sanctions can constrain your freedom to distribute copies of
237    programs internationally.  Software developers do not have the power to
238    eliminate or override these restrictions, but what they can and must do
239    is refuse to impose them as conditions of use of the program.  In this
240    way, the restrictions will not affect activities and people outside the
241    jurisdictions of these governments.  Thus, free software licenses
242    must not require obedience to any nontrivial export regulations as a
243    condition of exercising any of the essential freedoms.
244  </p>  </p>
245    
246  <p>  <p>
247  Please send FSF &amp; GNU inquiries to  Merely mentioning the existence of export regulations, without making
248  <a href="mailto:gnu@gnu.org"><em>gnu@gnu.org</em></a>.  them a condition of the license itself, is acceptable since it does
249  There are also <a href="/home.html#ContactInfo">other ways to contact</a>  not restrict users.  If an export regulation is actually trivial for
250  the FSF.  free software, then requiring it as a condition is not an actual
251  <br />  problem; however, it is a potential problem, since a later change in
252  Please send broken links and other corrections (or suggestions) to  export law could make the requirement nontrivial and thus render the
253  <a href="mailto:webmasters@gnu.org"><em>webmasters@gnu.org</em></a>.  software nonfree.
254  </p>  </p>
255    
256  <p>  <p>
257  Please see the  It is acceptable for a free license to specify which jurisdiction's
258  <a href="/server/standards/README.translations.html">Translations  law applies, or where litigation must be done, or both.
 README</a> for information on coordinating and submitting  
 translations of this article.  
259  </p>  </p>
260    
261  <p>  <p>
262  Copyright (C) 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004 Free  Most free software licenses are based on copyright, and there are limits
263  Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  on what kinds of requirements can be imposed through copyright.  If a
264  02111,  USA  copyright-based license respects freedom in the ways described above, it
265  <br />  is unlikely to have some other sort of problem that we never anticipated
266  Verbatim copying and distribution of this entire article is  (though this does happen occasionally).  However, some free software
267  permitted in any medium without royalty provided this notice is  licenses are based on contracts, and contracts can impose a much larger
268  preserved.  range of possible restrictions.  That means there are many possible ways
269    such a license could be unacceptably restrictive and nonfree.
270  </p>  </p>
271    
272  <p>  <p>
273  Updated:  We can't possibly list all the ways that might happen.  If a
274    contract-based license restricts the user in an unusual way that
275    copyright-based licenses cannot, and which isn't mentioned here as
276    legitimate, we will have to think about it, and we will probably conclude
277    it is nonfree.
278    </p>
279    
280    <p>
281    When talking about free software, it is best to avoid using terms
282    like &ldquo;give away&rdquo; or &ldquo;for free,&rdquo; because those terms imply that
283    the issue is about price, not freedom.  Some common terms such
284    as &ldquo;piracy&rdquo; embody opinions we hope you won't endorse.  See
285    <a href="/philosophy/words-to-avoid.html">Confusing Words and Phrases that
286    are Worth Avoiding</a> for a discussion of these terms.  We also have
287    a list of proper <a href="/philosophy/fs-translations.html">translations of
288    &ldquo;free software&rdquo;</a> into various languages.
289    </p>
290    
291    <p>
292    Finally, note that criteria such as those stated in this free software
293    definition require careful thought for their interpretation.  To decide
294    whether a specific software license qualifies as a free software license,
295    we judge it based on these criteria to determine whether it fits their
296    spirit as well as the precise words.  If a license includes unconscionable
297    restrictions, we reject it, even if we did not anticipate the issue
298    in these criteria.  Sometimes a license requirement raises an issue
299    that calls for extensive thought, including discussions with a lawyer,
300    before we can decide if the requirement is acceptable.  When we reach
301    a conclusion about a new issue, we often update these criteria to make
302    it easier to see why certain licenses do or don't qualify.
303    </p>
304    
305    <p>
306    If you are interested in whether a specific license qualifies as a free
307    software license, see our <a href="/licenses/license-list.html">list
308    of licenses</a>.  If the license you are concerned with is not
309    listed there, you can ask us about it by sending us email at
310    <a href="mailto:licensing@gnu.org">&lt;licensing@gnu.org&gt;</a>.
311    </p>
312    
313    <p>
314    If you are contemplating writing a new license, please contact the
315    Free Software Foundation first by writing to that address. The
316    proliferation of different free software licenses means increased work
317    for users in understanding the licenses; we may be able to help you
318    find an existing free software license that meets your needs.
319    </p>
320    
321    <p>
322    If that isn't possible, if you really need a new license, with our
323    help you can ensure that the license really is a free software license
324    and avoid various practical problems.
325    </p>
326    
327    <h3 id="beyond-software">Beyond Software</h3>
328    
329    <p>
330    <a href="/philosophy/free-doc.html">Software manuals must be free</a>,
331    for the same reasons that software must be free, and because the
332    manuals are in effect part of the software.
333    </p>
334    
335    <p>
336    The same arguments also make sense for other kinds of works of
337    practical use &mdash; that is to say, works that embody useful knowledge,
338    such as educational works and reference
339    works.  <a href="http://wikipedia.org">Wikipedia</a> is the best-known
340    example.
341    </p>
342    
343    <p>
344    Any kind of work <em>can</em> be free, and the definition of free software
345    has been extended to a definition of <a href="http://freedomdefined.org/">
346    free cultural works</a> applicable to any kind of works.
347    </p>
348    
349    <h3 id="open-source">Open Source?</h3>
350    
351    <p>
352    Another group has started using the term &ldquo;open source&rdquo; to mean
353    something close (but not identical) to &ldquo;free software&rdquo;.  We
354    prefer the term &ldquo;free software&rdquo; because, once you have heard that
355    it refers to freedom rather than price, it calls to mind freedom.  The
356    word &ldquo;open&rdquo; <a href="/philosophy/open-source-misses-the-point.html">
357    never refers to freedom</a>.
358    </p>
359    
360    <h3 id="History">History</h3>
361    
362    <p>From time to time we revise this Free Software Definition.  Here is
363    the list of substantive changes, along with links to show exactly what
364    was changed.</p>
365    
366    <ul>
367    
368    <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
369    1.129</a>: State explicitly that choice of law and choice of forum
370    specifications are allowed.  (This was always our policy.)</li>
371    
372    <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
373    1.122</a>: An export control requirement is a real problem if the
374    requirement is nontrivial; otherwise it is only a potential problem.</li>
375    
376    <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
377    1.118</a>: Clarification: the issue is limits on your right to modify,
378    not on what modifications you have made.  And modifications are not limited
379    to &ldquo;improvements&rdquo;</li>
380    
381    <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
382    1.111</a>: Clarify 1.77 by saying that only
383    retroactive <em>restrictions</em> are unacceptable.  The copyright
384    holders can always grant additional <em>permission</em> for use of the
385    work by releasing the work in another way in parallel.</li>
386    
387    <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
388    1.105</a>: Reflect, in the brief statement of freedom 1, the point
389    (already stated in version 1.80) that it includes really using your modified
390    version for your computing.</li>
391    
392    <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
393    1.92</a>: Clarify that obfuscated code does not qualify as source code.</li>
394    
395    <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
396    1.90</a>: Clarify that freedom 3 means the right to distribute copies
397    of your own modified or improved version, not a right to participate
398    in someone else's development project.</li>
399    
400    <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
401    1.89</a>: Freedom 3 includes the right to release modified versions as
402    free software.</li>
403    
404    <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
405    1.80</a>: Freedom 1 must be practical, not just theoretical;
406    i.e., no tivoization.</li>
407    
408    <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
409    1.77</a>: Clarify that all retroactive changes to the license are
410    unacceptable, even if it's not described as a complete
411    replacement.</li>
412    
413    <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
414    1.74</a>: Four clarifications of points not explicit enough, or stated
415    in some places but not reflected everywhere:
416    <ul>
417    <li>"Improvements" does not mean the license can
418    substantively limit what kinds of modified versions you can release.
419    Freedom 3 includes distributing modified versions, not just changes.</li>
420    <li>The right to merge in existing modules
421    refers to those that are suitably licensed.</li>
422    <li>Explicitly state the conclusion of the point about export controls.</li>
423    <li>Imposing a license change constitutes revoking the old license.</li>
424    </ul>
425    </li>
426    
427    <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
428    1.57</a>: Add &quot;Beyond Software&quot; section.</li>
429    
430    <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
431    1.46</a>: Clarify whose purpose is significant in the freedom to run
432    the program for any purpose.</li>
433    
434    <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
435    1.41</a>: Clarify wording about contract-based licenses.</li>
436    
437    <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
438    1.40</a>: Explain that a free license must allow to you use other
439    available free software to create your modifications.</li>
440    
441    <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
442    1.39</a>: Note that it is acceptable for a license to require you to
443    provide source for versions of the software you put into public
444    use.</li>
445    
446    <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
447    1.31</a>: Note that it is acceptable for a license to require you to
448    identify yourself as the author of modifications.  Other minor
449    clarifications throughout the text.</li>
450    
451    <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
452    1.23</a>: Address potential problems related to contract-based
453    licenses.</li>
454    
455    <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
456    1.16</a>: Explain why distribution of binaries is important.</li>
457    
458    <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
459    1.11</a>: Note that a free license may require you to send a copy of
460    versions you distribute to the author.</li>
461    
462    </ul>
463    
464    <p>There are gaps in the version numbers shown above because there are
465    other changes in this page that do not affect the definition or its
466    interpretations.  For instance, the list does not include changes in
467    asides, formatting, spelling, punctuation, or other parts of the page.
468    You can review the complete list of changes to the page through
469    the <a href="http://web.cvs.savannah.gnu.org/viewvc/www/philosophy/free-sw.html?root=www&amp;view=log">cvsweb
470    interface</a>.</p>
471    
472    
473    </div><!-- for id="content", starts in the include above -->
474    <!--#include virtual="/server/footer.html" -->
475    <div id="footer">
476    
477    <p>Please send general FSF &amp; GNU inquiries to
478    <a href="mailto:gnu@gnu.org">&lt;gnu@gnu.org&gt;</a>.
479    There are also <a href="/contact/">other ways to contact</a>
480    the FSF.  Broken links and other corrections or suggestions can be sent
481    to <a href="mailto:webmasters@gnu.org">&lt;webmasters@gnu.org&gt;</a>.</p>
482    
483    <p><!-- TRANSLATORS: Ignore the original text in this paragraph,
484            replace it with the translation of these two:
485    
486            We work hard and do our best to provide accurate, good quality
487            translations.  However, we are not exempt from imperfection.
488            Please send your comments and general suggestions in this regard
489            to <a href="mailto:web-translators@gnu.org">
490            &lt;web-translators@gnu.org&gt;</a>.</p>
491    
492            <p>For information on coordinating and submitting translations of
493            our web pages, see <a
494            href="/server/standards/README.translations.html">Translations
495            README</a>. -->
496    Please see the <a
497    href="/server/standards/README.translations.html">Translations
498    README</a> for information on coordinating and submitting translations
499    of this article.</p>
500    
501    <!-- Regarding copyright, in general, standalone pages (as opposed to
502         files generated as part of manuals) on the GNU web server should
503         be under CC BY-ND 3.0 US.  Please do NOT change or remove this
504         without talking with the webmasters or licensing team first.
505         Please make sure the copyright date is consistent with the
506         document.  For web pages, it is ok to list just the latest year the
507         document was modified, or published.
508        
509         If you wish to list earlier years, that is ok too.
510         Either "2001, 2002, 2003" or "2001-2003" are ok for specifying
511         years, as long as each year in the range is in fact a copyrightable
512         year, i.e., a year in which the document was published (including
513         being publicly visible on the web or in a revision control system).
514        
515         There is more detail about copyright years in the GNU Maintainers
516         Information document, www.gnu.org/prep/maintain. -->
517    
518    <p>Copyright &copy; 1996-2002, 2004-2007, 2009, 2010, 2012, 2013
519    Free Software Foundation, Inc.</p>
520    
521    <p>This page is licensed under a <a rel="license"
522    href="http://creativecommons.org/licenses/by-nd/3.0/us/">Creative
523    Commons Attribution-NoDerivs 3.0 United States License</a>.</p>
524    
525    <!--#include virtual="/server/bottom-notes.html" -->
526    
527    <p>Updated:
528  <!-- timestamp start -->  <!-- timestamp start -->
529  $Date$ $Author$  $Date$
530  <!-- timestamp end -->  <!-- timestamp end -->
531  </p>  </p>
532  </div>  </div>
533    </div>
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