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<A HREF="/philosophy/free-sw.nl.html">Dutch</A> |
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| <A HREF="/philosophy/free-sw.html">English</A> |
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| <A HREF="/philosophy/free-sw.fr.html">French</A> |
<h2>What is free software?</h2> |
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| <A HREF="/philosophy/free-sw.it.html">Italian</A> |
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| <A HREF="/philosophy/free-sw.ja.html">Japanese</A> |
<div class="article"> |
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| <A HREF="/philosophy/free-sw.ko.html">Korean</A> |
<h3>The Free Software Definition</h3> |
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| <A HREF="/philosophy/free-sw.no.html">Norwegian</A> |
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| <A HREF="/philosophy/free-sw.pt.html">Portuguese</A> |
<blockquote class="note" id="fsf-licensing"><p style="font-size: 80%"> |
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| <A HREF="/philosophy/free-sw.ru.html">Russian</A> |
Have a question about free software licensing not answered here? |
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| <A HREF="/philosophy/free-sw.es.html">Spanish</A> |
See our other <a href="http://www.fsf.org/licensing">licensing resources</a>, |
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| <A HREF="/philosophy/free-sw.tr.html">Turkish</A> |
and if necessary contact the FSF Compliance Lab |
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] |
at <a href="mailto:licensing@fsf.org">licensing@fsf.org</a>.</p> |
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<P> |
</blockquote> |
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We maintain this free software definition to show clearly what must be |
<div class="comment"> |
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true about a particular software program for it to be considered |
<p> |
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``free software''. |
The free software definition presents the criteria for whether a |
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particular software program qualifies as free software. From time to |
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<P> |
time we revise this definition, to clarify it or to resolve questions |
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about subtle issues. See the <a href="#History">History section</a> |
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``Free software'' is a matter of liberty, not price. To understand |
below for a list of changes that affect the definition of free |
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the concept, you should think of ``free speech'', not ``free beer.'' |
software. |
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<P> |
</p> |
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``Free software'' refers to the users' freedom to run, copy, |
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distribute, study, change and improve the software. More precisely, |
<p> |
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it refers to four kinds of freedom, for the users of the software: |
“Open source” is something different: it has a very |
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<P> |
different philosophy based on different values. Its practical |
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definition is different too, but nearly all open source programs are |
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<UL> |
in fact free. We explain the |
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<LI>The freedom to run the program, for any purpose (freedom 0). |
difference in <a href="/philosophy/open-source-misses-the-point.html"> |
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<LI>The freedom to study how the program works, and adapt it to your needs |
Why “Open Source” misses the point of Free Software</a>. |
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(freedom 1). Access to the source code is a precondition for this. |
</p> |
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<LI>The freedom to redistribute copies so you can help your neighbor |
</div> |
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<p> |
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“Free software” means software that respects users' |
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freedom and community. Roughly, it means that <b>the users have the |
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freedom to run, copy, distribute, study, change and improve the |
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software</b>. Thus, “free software” is a matter of |
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liberty, not price. To understand the concept, you should think of |
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“free” as in “free speech,” not as in |
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“free beer”. We sometimes call it “libre |
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software,” borrowing the French or Spanish word for |
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“free” as in freedom, to show we do not mean the software |
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is gratis. |
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</p> |
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<p> |
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We campaign for these freedoms because everyone deserves them. With |
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these freedoms, the users (both individually and collectively) control |
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the program and what it does for them. When users don't control the |
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program, we call it a “nonfree” or |
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“proprietary” program. The nonfree program controls the |
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users, and the developer controls the program; this makes the |
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program <a href="/philosophy/free-software-even-more-important.html"> |
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an instrument of unjust power</a>. |
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</p> |
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|
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<h4> The four essential freedoms</h4> |
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<p> |
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A program is free software if the program's users have the |
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four essential freedoms: <a href="#f1">[1]</a> |
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</p> |
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<ul class="important"> |
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<li>The freedom to run the program as you wish, |
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for any purpose (freedom 0).</li> |
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<li>The freedom to study how the program works, and change it so it |
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does your computing as you wish (freedom 1). Access to the source |
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code is a precondition for this. |
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</li> |
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<li>The freedom to redistribute copies so you can help others |
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(freedom 2). |
(freedom 2). |
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<LI>The freedom to improve the program, and release your improvements |
</li> |
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to the public, so that the whole community benefits. |
<li>The freedom to distribute copies of your modified versions |
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(freedom 3). Access to the source code is a precondition for this. |
to others (freedom 3). By doing this you can give the whole |
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</UL> |
community a chance to benefit from your changes. |
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Access to the source code is a precondition for this. |
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<P> |
</li> |
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A program is free software if users have all of these freedoms. |
</ul> |
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Thus, you should be free to redistribute copies, either with or |
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without modifications, either gratis or charging a fee for |
<p> |
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distribution, to <A HREF="#exportcontrol">anyone anywhere</A>. Being |
A program is free software if it gives users adequately all of these |
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free to do these things means (among other things) that you do not |
freedoms. Otherwise, it is nonfree. While we can distinguish various |
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have to ask or pay for permission. |
nonfree distribution schemes in terms of how far they fall short of |
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being free, we consider them all equally unethical.</p> |
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<p>In any given scenario, these freedoms must apply to whatever code |
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we plan to make use of, or lead others to make use of. For instance, |
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consider a program A which automatically launches a program B to |
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handle some cases. If we plan to distribute A as it stands, that |
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implies users will need B, so we need to judge whether both A and B |
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are free. However, if we plan to modify A so that it doesn't use B, |
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only A needs to be free; B is not pertinent to that plan.</p> |
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<p> |
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“Free software” does not mean “noncommercial”. A free |
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program must be available for commercial use, commercial development, |
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and commercial distribution. Commercial development of free software |
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is no longer unusual; such free commercial software is very important. |
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You may have paid money to get copies of free software, or you may have |
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obtained copies at no charge. But regardless of how you got your copies, |
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you always have the freedom to copy and change the software, even to |
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<a href="/philosophy/selling.html">sell copies</a>. |
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</p> |
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<p> |
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A free program must offer the four freedoms to any user that obtains a |
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copy of the software, provided the user has complied thus far with the |
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conditions of the free license covering the software. Putting some of |
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the freedoms off limits to some users, or requiring that users pay, in |
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money or in kind, to exercise them, is tantamount to not granting the |
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freedoms in question, and thus renders the program nonfree. |
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</p> |
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<h3>Clarifying the line at various points</h3> |
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<p>In the rest of this article we expain more precisely how far the |
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various freedoms need to extend, on various issues, in order for a |
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program to be free.</p> |
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<h4>The freedom to run the program as you wish</h4> |
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<p> |
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The freedom to run the program means the freedom for any kind of person |
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or organization to use it on any kind of computer system, for any kind of |
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overall job and purpose, without being required to communicate about it |
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with the developer or any other specific entity. In this freedom, it is |
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the <em>user's</em> purpose that matters, not the <em>developer's</em> |
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purpose; you as a user are free to run the program for your purposes, |
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and if you distribute it to someone else, she is then free to run it |
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for her purposes, but you are not entitled to impose your purposes on her. |
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</p> |
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<p> |
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The freedom to run the program as you wish means that you are not |
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forbidden or stopped from making it run. This has nothing to do with what |
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functionality the program has, whether it is technically capable of |
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functioning in any given environment, or whether it is useful for any |
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particular computing activity.</p> |
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<p>For example, if the code arbitrarily rejects certain meaningful |
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inputs—or even fails unconditionally—that may make the |
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program less useful, perhaps even totally useless, but it does not |
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deny users the freedom to run the program, so it does not conflict |
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with freedom 0. If the program is free, the users can overcome the |
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loss of usefulness, because freedoms 1 and 3 permit users and |
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communities to make and distribute modified versions without the |
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arbitrary nuisance code.</p> |
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<h4>The freedom to study the source code and make changes</h4> |
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<p> |
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In order for freedoms 1 and 3 (the freedom to make changes and the |
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freedom to publish the changed versions) to be meaningful, you need to have |
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access to the source code of the program. Therefore, accessibility of |
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source code is a necessary condition for free software. Obfuscated |
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“source code” is not real source code and does not count |
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as source code. |
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</p> |
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<p> |
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Freedom 1 includes the freedom to use your changed version in place of |
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the original. If the program is delivered in a product designed to |
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run someone else's modified versions but refuse to run yours — a |
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practice known as “tivoization” or “lockdown”, |
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or (in its practitioners' perverse terminology) as “secure |
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boot” — freedom 1 becomes an empty pretense rather than a |
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practical reality. These binaries are not free |
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software even if the source code they are compiled from is free. |
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</p> |
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<p> |
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One important way to modify a program is by merging in available free |
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subroutines and modules. If the program's license says that you |
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cannot merge in a suitably licensed existing module — for instance, if it |
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requires you to be the copyright holder of any code you add — then the |
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license is too restrictive to qualify as free. |
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</p> |
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<p> |
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Whether a change constitutes an improvement is a subjective matter. |
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If your right to modify a program is limited, in substance, to changes that |
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someone else considers an improvement, that program is not free. |
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</p> |
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<h4>The freedom to redistribute if you wish: basic requirements</h4> |
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<p>Freedom to distribute (freedoms 2 and 3) means you are free to |
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redistribute copies, either with or without modifications, either |
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gratis or charging a fee for distribution, to |
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<a href="#exportcontrol">anyone anywhere</a>. Being free to do these |
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things means (among other things) that you do not have to ask or pay |
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for permission to do so. |
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</p> |
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<P> |
<p> |
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You should also have the freedom to make modifications and use them |
You should also have the freedom to make modifications and use them |
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privately in your own work or play, without even mentioning that they |
privately in your own work or play, without even mentioning that they |
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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 |
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notify anyone in particular, or in any particular way. |
notify anyone in particular, or in any particular way. |
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</p> |
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<P> |
<p> |
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The freedom to use a program means the freedom for any kind of person |
Freedom 3 includes the freedom to release your modified versions |
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or organization to use it on any kind of computer system, for any kind |
as free software. A free license may also permit other ways of |
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of overall job, and without being required to communicate subsequently |
releasing them; in other words, it does not have to be |
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with the developer or any other specific entity. |
a <a href="/copyleft/copyleft.html">copyleft</a> license. However, a |
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license that requires modified versions to be nonfree does not qualify |
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as a free license. |
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</p> |
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<P> |
<p> |
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The freedom to redistribute copies must include binary or executable |
The freedom to redistribute copies must include binary or executable |
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forms of the program, as well as source code. (It is ok if there is |
forms of the program, as well as source code, for both modified and |
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no way to produce a binary or executable form, but people must have |
unmodified versions. (Distributing programs in runnable form is necessary |
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the freedom to redistribute such forms should they find a way to make |
for conveniently installable free operating systems.) It is OK if there |
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them.) |
is no way to produce a binary or executable form for a certain program |
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(since some languages don't support that feature), but you must have the |
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<P> |
freedom to redistribute such forms should you find or develop a way to |
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In order for the freedoms to make changes, and to publish improved |
make them. |
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versions, to be meaningful, you must have access to the source code of |
</p> |
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the program. Therefore, accessibility of source code is a necessary |
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condition for free software. |
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<P> |
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In order for these freedoms to be real, they must be irrevocable as |
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long as you do nothing wrong; if the developer of the software has the |
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power to revoke the license, without your doing anything to give |
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cause, the software is not free. |
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<P> |
<h4>Copyleft</h4> |
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However, certain kinds of rules about the manner of distributing free |
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<p> |
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Certain kinds of rules about the manner of distributing free |
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software are acceptable, when they don't conflict with the central |
software are acceptable, when they don't conflict with the central |
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freedoms. For example, copyleft (very simply stated) is the rule that |
freedoms. For example, <a href="/copyleft/copyleft.html">copyleft</a> |
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when redistributing the program, you cannot add restrictions to deny |
(very simply stated) is the rule that when redistributing the program, |
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other people the central freedoms. This rule does not conflict with |
you cannot add restrictions to deny other people the central freedoms. |
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the central freedoms; rather it protects them. |
This rule does not conflict with the central freedoms; rather it |
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protects them. |
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<P> |
</p> |
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Thus, you may have paid money to get copies of GNU software, or you |
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may have obtained copies at no charge. But regardless of how you got |
<p> |
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your copies, you always have the freedom to copy and change the |
In the GNU project, we use copyleft to protect the four freedoms |
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software, even to <A HREF="/philosophy/selling.html">sell copies</A>. |
legally for everyone. We believe there are important reasons why |
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<a href="/philosophy/pragmatic.html">it is better to use |
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<P> |
copyleft</a>. However, |
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``Free software'' does not mean ``non-commercial''. A free program |
<a href="/philosophy/categories.html#Non-CopyleftedFreeSoftware"> |
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must be available for commercial use. Commercial development of free |
noncopylefted free software</a> is ethical |
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software is no longer unusual; such programs are free commercial |
too. See <a href="/philosophy/categories.html">Categories of Free |
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software. |
Software</a> for a description of how “free software,” |
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“copylefted software” and other categories of software |
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relate to each other. |
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</p> |
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<h4>Rules about packaging and distribution details</h4> |
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<p> |
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Rules about how to package a modified version are acceptable, |
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if they don't substantively limit your freedom to release modified |
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versions, or your freedom to make and use modified versions privately. |
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Thus, it is acceptable for the license to require that you change the |
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name of the modified version, remove a logo, or identify your |
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modifications as yours. As long as these requirements are not so |
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burdensome that they effectively hamper you from releasing your |
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changes, they are acceptable; you're already making other changes to |
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the program, so you won't have trouble making a few more. |
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</p> |
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<p> |
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Rules that “if you make your version available in this way, you |
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must make it available in that way also” can be acceptable too, |
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on the same condition. An example of such an acceptable rule is one |
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saying that if you have distributed a |
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modified version and a previous developer asks for a copy of it, you |
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must send one. (Note that such a rule still leaves you the choice of |
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whether to distribute your version at all.) Rules that require release |
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of source code to the users for versions that you put into public use |
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are also acceptable. |
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</p> |
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<p> |
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A special issue arises when a license requires changing the name by |
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which the program will be invoked from other programs. That |
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effectively hampers you from releasing your changed version so that it |
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can replace the original when invoked by those other programs. This |
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sort of requirement is acceptable only if there's a suitable aliasing |
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facility that allows you to specify the original program's name as an |
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alias for the modified version.</p> |
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<h4>Export regulations</h4> |
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<p> |
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Sometimes government <a id="exportcontrol">export control regulations</a> |
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and trade sanctions can constrain your freedom to distribute copies of |
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programs internationally. Software developers do not have the power to |
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eliminate or override these restrictions, but what they can and must do |
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is refuse to impose them as conditions of use of the program. In this |
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way, the restrictions will not affect activities and people outside the |
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jurisdictions of these governments. Thus, free software licenses |
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must not require obedience to any nontrivial export regulations as a |
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condition of exercising any of the essential freedoms. |
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</p> |
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<p> |
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Merely mentioning the existence of export regulations, without making |
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them a condition of the license itself, is acceptable since it does |
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not restrict users. If an export regulation is actually trivial for |
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free software, then requiring it as a condition is not an actual |
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problem; however, it is a potential problem, since a later change in |
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export law could make the requirement nontrivial and thus render the |
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software nonfree. |
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</p> |
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<h4>Legal considerations</h4> |
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<p> |
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In order for these freedoms to be real, they must be permanent and |
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irrevocable as long as you do nothing wrong; if the developer of the |
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software has the power to revoke the license, or retroactively add |
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restrictions to its terms, without your doing anything wrong to give |
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cause, the software is not free. |
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</p> |
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<P> |
<p> |
| 334 |
Rules about how to package a modified version are acceptable, if they |
A free license may not require compliance with the license of a |
| 335 |
don't effectively block your freedom to release modified versions. |
nonfree program. Thus, for instance, if a license requires you to |
| 336 |
Rules that ``if you make the program available in this way, you must |
comply with the licenses of “all the programs you use”, in |
| 337 |
make it available in that way also'' can be acceptable too, on the |
the case of a user that runs nonfree programs this would require |
| 338 |
same condition. (Note that such a rule still leaves you the choice of |
compliance with the licenses of those nonfree programs; that makes the |
| 339 |
whether to publish the program or not.) |
license nonfree. |
| 340 |
|
</p> |
| 341 |
<P> |
|
| 342 |
In the GNU project, we use <A HREF="/copyleft/copyleft.html"> |
<p> |
| 343 |
``copyleft''</A> to protect these freedoms legally for everyone. But |
It is acceptable for a free license to specify which jurisdiction's |
| 344 |
<A HREF="/philosophy/categories.html#Non-CopyleftedFreeSoftware"> |
law applies, or where litigation must be done, or both. |
| 345 |
non-copylefted free software</A> also exists. We believe there are |
</p> |
| 346 |
important reasons why <A HREF="/philosophy/pragmatic.html"> it is |
|
| 347 |
better to use copyleft</A>, but if your program is non-copylefted free |
<h4>Contract-based licenses</h4> |
| 348 |
software, we can still use it. |
|
| 349 |
|
<p> |
| 350 |
<P> |
Most free software licenses are based on copyright, and there are limits |
| 351 |
See <A HREF="/philosophy/categories.html">Categories of Free Software |
on what kinds of requirements can be imposed through copyright. If a |
| 352 |
(18k characters)</A> |
copyright-based license respects freedom in the ways described above, it |
| 353 |
for a description of how ``free software,'' ``copylefted software'' and |
is unlikely to have some other sort of problem that we never anticipated |
| 354 |
other categories of software relate to each other. |
(though this does happen occasionally). However, some free software |
| 355 |
|
licenses are based on contracts, and contracts can impose a much larger |
| 356 |
<P> |
range of possible restrictions. That means there are many possible ways |
| 357 |
Sometimes government <A NAME="exportcontrol">export control |
such a license could be unacceptably restrictive and nonfree. |
| 358 |
regulations</A> and trade sanctions can constrain your freedom to |
</p> |
| 359 |
distribute copies of programs internationally. Software developers do |
|
| 360 |
not have the power to eliminate or override these restrictions, but |
<p> |
| 361 |
what they can and must do is refuse to impose them as conditions of |
We can't possibly list all the ways that might happen. If a |
| 362 |
use of the program. In this way, the restrictions will not affect |
contract-based license restricts the user in an unusual way that |
| 363 |
activities and people outside the jurisdictions of these governments. |
copyright-based licenses cannot, and which isn't mentioned here as |
| 364 |
|
legitimate, we will have to think about it, and we will probably conclude |
| 365 |
<P> |
it is nonfree. |
| 366 |
When talking about free software, it is best to avoid using terms like |
</p> |
| 367 |
``give away'' or ``for free'', because those terms imply that the |
|
| 368 |
issue is about price, not freedom. Some common terms such as |
<h4>Use the right words when talking about free software</h4> |
| 369 |
``piracy'' embody opinions we hope you won't endorse. See <A |
|
| 370 |
HREF="/philosophy/words-to-avoid.html">Confusing Words and Phrases |
<p> |
| 371 |
that are Worth Avoiding</A> for a discussion of these terms. |
When talking about free software, it is best to avoid using terms |
| 372 |
We also have a list of <A HREF="/philosophy/fs-translations.html">translations |
like “give away” or “for free,” because those terms imply that |
| 373 |
of "free software"</A> into various languages. |
the issue is about price, not freedom. Some common terms such |
| 374 |
|
as “piracy” embody opinions we hope you won't endorse. See |
| 375 |
|
<a href="/philosophy/words-to-avoid.html">Confusing Words and Phrases that |
| 376 |
|
are Worth Avoiding</a> for a discussion of these terms. We also have |
| 377 |
|
a list of proper <a href="/philosophy/fs-translations.html">translations of |
| 378 |
|
“free software”</a> into various languages. |
| 379 |
|
</p> |
| 380 |
|
|
| 381 |
<P> |
<h4>How we interpret these criteria</h4> |
| 382 |
|
|
| 383 |
|
<p> |
| 384 |
Finally, note that criteria such as those stated in this free software |
Finally, note that criteria such as those stated in this free software |
| 385 |
definition require careful thought for their interpretation. To |
definition require careful thought for their interpretation. To decide |
| 386 |
decide whether a specific software license qualifies as a free |
whether a specific software license qualifies as a free software license, |
| 387 |
software license, we judge it based on these criteria to determine |
we judge it based on these criteria to determine whether it fits their |
| 388 |
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 |
| 389 |
license includes unconscionable restrictions, we reject it, even if we |
restrictions, we reject it, even if we did not anticipate the issue |
| 390 |
did not anticipate the issue in these criteria. Sometimes a license |
in these criteria. Sometimes a license requirement raises an issue |
| 391 |
requirement raises an issue that calls for extensive thought before we |
that calls for extensive thought, including discussions with a lawyer, |
| 392 |
can decide if the requirement is acceptable, including discussions |
before we can decide if the requirement is acceptable. When we reach |
| 393 |
with a lawyer. When we reach a conclusion, we sometimes update these |
a conclusion about a new issue, we often update these criteria to make |
| 394 |
criteria to make it easier to see why certain licenses do or don't |
it easier to see why certain licenses do or don't qualify. |
| 395 |
qualify. |
</p> |
| 396 |
|
|
| 397 |
<P> |
<h4>Get help with free licenses</h4> |
| 398 |
|
|
| 399 |
If you are interested in whether a specific license qualifies as a |
<p> |
| 400 |
free software license, see our <A |
If you are interested in whether a specific license qualifies as a free |
| 401 |
HREF="/philosophy/license-list.html"> list of licenses </A>. If the |
software license, see our <a href="/licenses/license-list.html">list |
| 402 |
license you are concerned with is not listed there, you can ask us |
of licenses</a>. If the license you are concerned with is not |
| 403 |
about it by sending us email at <A |
listed there, you can ask us about it by sending us email at |
| 404 |
HREF="mailto:licensing@gnu.org"><licensing@gnu.org></A>. |
<a href="mailto:licensing@gnu.org"><licensing@gnu.org></a>. |
| 405 |
|
</p> |
| 406 |
<HR> |
|
| 407 |
|
<p> |
| 408 |
<H4><A HREF="/philosophy/philosophy.html">Other Texts to Read</A></H4> |
If you are contemplating writing a new license, please contact the |
| 409 |
|
Free Software Foundation first by writing to that address. The |
| 410 |
<P> |
proliferation of different free software licenses means increased work |
| 411 |
Another group has started using the term <A |
for users in understanding the licenses; we may be able to help you |
| 412 |
HREF="free-software-for-freedom.html"> open source</A> to mean |
find an existing free software license that meets your needs. |
| 413 |
something close (but not identical) to "free software". |
</p> |
| 414 |
|
|
| 415 |
<HR> |
<p> |
| 416 |
|
If that isn't possible, if you really need a new license, with our |
| 417 |
Return to <A HREF="/home.html">GNU's home page</A>. |
help you can ensure that the license really is a free software license |
| 418 |
<P> |
and avoid various practical problems. |
| 419 |
FSF & GNU inquiries & questions to |
</p> |
| 420 |
<A HREF="mailto:gnu@gnu.org"><EM>gnu@gnu.org</EM></A>. |
|
| 421 |
Other <A HREF="/home.html#ContactInfo">ways to contact</A> the FSF. |
<h3 id="beyond-software">Beyond Software</h3> |
| 422 |
<P> |
|
| 423 |
Comments on these web pages to |
<p> |
| 424 |
<A HREF="mailto:webmasters@www.gnu.org"><EM>webmasters@www.gnu.org</EM></A>, |
<a href="/philosophy/free-doc.html">Software manuals must be free</a>, |
| 425 |
send other questions to |
for the same reasons that software must be free, and because the |
| 426 |
<A HREF="mailto:gnu@gnu.org"><EM>gnu@gnu.org</EM></A>. |
manuals are in effect part of the software. |
| 427 |
<P> |
</p> |
| 428 |
Copyright (C) 1996, 1997, 1998, 1999, 2000, 2001 Free Software Foundation, Inc., |
|
| 429 |
59 Temple Place - Suite 330, Boston, MA 02111, USA |
<p> |
| 430 |
<P> |
The same arguments also make sense for other kinds of works of |
| 431 |
Verbatim copying and distribution of this entire article is |
practical use — that is to say, works that embody useful knowledge, |
| 432 |
permitted in any medium, provided this notice is preserved.<P> |
such as educational works and reference |
| 433 |
Updated: |
works. <a href="http://wikipedia.org">Wikipedia</a> is the best-known |
| 434 |
<!-- hhmts start --> |
example. |
| 435 |
21 Feb 2001 bkuhn |
</p> |
| 436 |
<!-- hhmts end --> |
|
| 437 |
<HR> |
<p> |
| 438 |
</BODY> |
Any kind of work <em>can</em> be free, and the definition of free software |
| 439 |
</HTML> |
has been extended to a definition of <a href="http://freedomdefined.org/"> |
| 440 |
|
free cultural works</a> applicable to any kind of works. |
| 441 |
|
</p> |
| 442 |
|
|
| 443 |
|
<h3 id="open-source">Open Source?</h3> |
| 444 |
|
|
| 445 |
|
<p> |
| 446 |
|
Another group uses the term “open source” to mean |
| 447 |
|
something close (but not identical) to “free software”. We |
| 448 |
|
prefer the term “free software” because, once you have heard that |
| 449 |
|
it refers to freedom rather than price, it calls to mind freedom. The |
| 450 |
|
word “open” <a href="/philosophy/open-source-misses-the-point.html"> |
| 451 |
|
never refers to freedom</a>. |
| 452 |
|
</p> |
| 453 |
|
</div> |
| 454 |
|
|
| 455 |
|
<h3 id="History">History</h3> |
| 456 |
|
|
| 457 |
|
<p>From time to time we revise this Free Software Definition. Here is |
| 458 |
|
the list of substantive changes, along with links to show exactly what |
| 459 |
|
was changed.</p> |
| 460 |
|
|
| 461 |
|
<ul> |
| 462 |
|
|
| 463 |
|
<li><a href="http://web.cvs.savannah.gnu.org/viewvc/www/philosophy/free-sw.html?root=www&r1=1.164&r2=1.165">Version |
| 464 |
|
1.165</a>: Clarify that arbitrary annoyances in the code do not |
| 465 |
|
negate freedom 0, and that freedoms 1 and 3 enable users to remove them.</li> |
| 466 |
|
|
| 467 |
|
<li><a href="http://web.cvs.savannah.gnu.org/viewvc/www/philosophy/free-sw.html?root=www&r1=1.152&r2=1.153">Version |
| 468 |
|
1.153</a>: Clarify that freedom to run the program means nothing stops |
| 469 |
|
you from making it run.</li> |
| 470 |
|
|
| 471 |
|
<li><a href="http://web.cvs.savannah.gnu.org/viewvc/www/philosophy/free-sw.html?root=www&r1=1.140&r2=1.141">Version |
| 472 |
|
1.141</a>: Clarify which code needs to be free.</li> |
| 473 |
|
|
| 474 |
|
<li><a href="http://web.cvs.savannah.gnu.org/viewvc/www/philosophy/free-sw.html?root=www&r1=1.134&r2=1.135">Version |
| 475 |
|
1.135</a>: Say each time that freedom 0 is the freedom to run the program |
| 476 |
|
as you wish.</li> |
| 477 |
|
|
| 478 |
|
<li><a href="http://web.cvs.savannah.gnu.org/viewvc/www/philosophy/free-sw.html?root=www&r1=1.133&r2=1.134">Version |
| 479 |
|
1.134</a>: Freedom 0 is not a matter of the program's functionality.</li> |
| 480 |
|
|
| 481 |
|
<li><a href="http://web.cvs.savannah.gnu.org/viewvc/www/philosophy/free-sw.html?root=www&r1=1.130&r2=1.131">Version |
| 482 |
|
1.131</a>: A free license may not require compliance with a nonfree license |
| 483 |
|
of another program.</li> |
| 484 |
|
|
| 485 |
|
<li><a href="http://web.cvs.savannah.gnu.org/viewvc/www/philosophy/free-sw.html?root=www&r1=1.128&r2=1.129">Version |
| 486 |
|
1.129</a>: State explicitly that choice of law and choice of forum |
| 487 |
|
specifications are allowed. (This was always our policy.)</li> |
| 488 |
|
|
| 489 |
|
<li><a href="http://web.cvs.savannah.gnu.org/viewvc/www/philosophy/free-sw.html?root=www&r1=1.121&r2=1.122">Version |
| 490 |
|
1.122</a>: An export control requirement is a real problem if the |
| 491 |
|
requirement is nontrivial; otherwise it is only a potential problem.</li> |
| 492 |
|
|
| 493 |
|
<li><a href="http://web.cvs.savannah.gnu.org/viewvc/www/philosophy/free-sw.html?root=www&r1=1.117&r2=1.118">Version |
| 494 |
|
1.118</a>: Clarification: the issue is limits on your right to modify, |
| 495 |
|
not on what modifications you have made. And modifications are not limited |
| 496 |
|
to “improvements”</li> |
| 497 |
|
|
| 498 |
|
<li><a href="http://web.cvs.savannah.gnu.org/viewvc/www/philosophy/free-sw.html?root=www&r1=1.110&r2=1.111">Version |
| 499 |
|
1.111</a>: Clarify 1.77 by saying that only |
| 500 |
|
retroactive <em>restrictions</em> are unacceptable. The copyright |
| 501 |
|
holders can always grant additional <em>permission</em> for use of the |
| 502 |
|
work by releasing the work in another way in parallel.</li> |
| 503 |
|
|
| 504 |
|
<li><a href="http://web.cvs.savannah.gnu.org/viewvc/www/philosophy/free-sw.html?root=www&r1=1.104&r2=1.105">Version |
| 505 |
|
1.105</a>: Reflect, in the brief statement of freedom 1, the point |
| 506 |
|
(already stated in version 1.80) that it includes really using your modified |
| 507 |
|
version for your computing.</li> |
| 508 |
|
|
| 509 |
|
<li><a href="http://web.cvs.savannah.gnu.org/viewvc/www/philosophy/free-sw.html?root=www&r1=1.91&r2=1.92">Version |
| 510 |
|
1.92</a>: Clarify that obfuscated code does not qualify as source code.</li> |
| 511 |
|
|
| 512 |
|
<li><a href="http://web.cvs.savannah.gnu.org/viewvc/www/philosophy/free-sw.html?root=www&r1=1.89&r2=1.90">Version |
| 513 |
|
1.90</a>: Clarify that freedom 3 means the right to distribute copies |
| 514 |
|
of your own modified or improved version, not a right to participate |
| 515 |
|
in someone else's development project.</li> |
| 516 |
|
|
| 517 |
|
<li><a href="http://web.cvs.savannah.gnu.org/viewvc/www/philosophy/free-sw.html?root=www&r1=1.88&r2=1.89">Version |
| 518 |
|
1.89</a>: Freedom 3 includes the right to release modified versions as |
| 519 |
|
free software.</li> |
| 520 |
|
|
| 521 |
|
<li><a href="http://web.cvs.savannah.gnu.org/viewvc/www/philosophy/free-sw.html?root=www&r1=1.79&r2=1.80">Version |
| 522 |
|
1.80</a>: Freedom 1 must be practical, not just theoretical; |
| 523 |
|
i.e., no tivoization.</li> |
| 524 |
|
|
| 525 |
|
<li><a href="http://web.cvs.savannah.gnu.org/viewvc/www/philosophy/free-sw.html?root=www&r1=1.76&r2=1.77">Version |
| 526 |
|
1.77</a>: Clarify that all retroactive changes to the license are |
| 527 |
|
unacceptable, even if it's not described as a complete |
| 528 |
|
replacement.</li> |
| 529 |
|
|
| 530 |
|
<li><a href="http://web.cvs.savannah.gnu.org/viewvc/www/philosophy/free-sw.html?root=www&r1=1.73&r2=1.74">Version |
| 531 |
|
1.74</a>: Four clarifications of points not explicit enough, or stated |
| 532 |
|
in some places but not reflected everywhere: |
| 533 |
|
<ul> |
| 534 |
|
<li>"Improvements" does not mean the license can |
| 535 |
|
substantively limit what kinds of modified versions you can release. |
| 536 |
|
Freedom 3 includes distributing modified versions, not just changes.</li> |
| 537 |
|
<li>The right to merge in existing modules |
| 538 |
|
refers to those that are suitably licensed.</li> |
| 539 |
|
<li>Explicitly state the conclusion of the point about export controls.</li> |
| 540 |
|
<li>Imposing a license change constitutes revoking the old license.</li> |
| 541 |
|
</ul> |
| 542 |
|
</li> |
| 543 |
|
|
| 544 |
|
<li><a href="http://web.cvs.savannah.gnu.org/viewvc/www/philosophy/free-sw.html?root=www&r1=1.56&r2=1.57">Version |
| 545 |
|
1.57</a>: Add "Beyond Software" section.</li> |
| 546 |
|
|
| 547 |
|
<li><a href="http://web.cvs.savannah.gnu.org/viewvc/www/philosophy/free-sw.html?root=www&r1=1.45&r2=1.46">Version |
| 548 |
|
1.46</a>: Clarify whose purpose is significant in the freedom to run |
| 549 |
|
the program for any purpose.</li> |
| 550 |
|
|
| 551 |
|
<li><a href="http://web.cvs.savannah.gnu.org/viewvc/www/philosophy/free-sw.html?root=www&r1=1.40&r2=1.41">Version |
| 552 |
|
1.41</a>: Clarify wording about contract-based licenses.</li> |
| 553 |
|
|
| 554 |
|
<li><a href="http://web.cvs.savannah.gnu.org/viewvc/www/philosophy/free-sw.html?root=www&r1=1.39&r2=1.40">Version |
| 555 |
|
1.40</a>: Explain that a free license must allow to you use other |
| 556 |
|
available free software to create your modifications.</li> |
| 557 |
|
|
| 558 |
|
<li><a href="http://web.cvs.savannah.gnu.org/viewvc/www/philosophy/free-sw.html?root=www&r1=1.38&r2=1.39">Version |
| 559 |
|
1.39</a>: Note that it is acceptable for a license to require you to |
| 560 |
|
provide source for versions of the software you put into public |
| 561 |
|
use.</li> |
| 562 |
|
|
| 563 |
|
<li><a href="http://web.cvs.savannah.gnu.org/viewvc/www/philosophy/free-sw.html?root=www&r1=1.30&r2=1.31">Version |
| 564 |
|
1.31</a>: Note that it is acceptable for a license to require you to |
| 565 |
|
identify yourself as the author of modifications. Other minor |
| 566 |
|
clarifications throughout the text.</li> |
| 567 |
|
|
| 568 |
|
<li><a href="http://web.cvs.savannah.gnu.org/viewvc/www/philosophy/free-sw.html?root=www&r1=1.22&r2=1.23">Version |
| 569 |
|
1.23</a>: Address potential problems related to contract-based |
| 570 |
|
licenses.</li> |
| 571 |
|
|
| 572 |
|
<li><a href="http://web.cvs.savannah.gnu.org/viewvc/www/philosophy/free-sw.html?root=www&r1=1.15&r2=1.16">Version |
| 573 |
|
1.16</a>: Explain why distribution of binaries is important.</li> |
| 574 |
|
|
| 575 |
|
<li><a href="http://web.cvs.savannah.gnu.org/viewvc/www/philosophy/free-sw.html?root=www&r1=1.10&r2=1.11">Version |
| 576 |
|
1.11</a>: Note that a free license may require you to send a copy of |
| 577 |
|
versions you distribute to previous developers on request.</li> |
| 578 |
|
|
| 579 |
|
</ul> |
| 580 |
|
|
| 581 |
|
<p>There are gaps in the version numbers shown above because there are |
| 582 |
|
other changes in this page that do not affect the definition or its |
| 583 |
|
interpretations. For instance, the list does not include changes in |
| 584 |
|
asides, formatting, spelling, punctuation, or other parts of the page. |
| 585 |
|
You can review the complete list of changes to the page through |
| 586 |
|
the <a href="http://web.cvs.savannah.gnu.org/viewvc/www/philosophy/free-sw.html?root=www&view=log">cvsweb |
| 587 |
|
interface</a>.</p> |
| 588 |
|
|
| 589 |
|
<h3 style="font-size:1em">Footnote</h3> |
| 590 |
|
<ol> |
| 591 |
|
<li id="f1">The reason they are numbered 0, 1, 2 and 3 is historical. Around |
| 592 |
|
1990 there were three freedoms, numbered 1, 2 and 3. Then we realized that |
| 593 |
|
the freedom to run the program needed to be mentioned explicitly. |
| 594 |
|
It was clearly more basic than the other three, so it properly should |
| 595 |
|
precede them. Rather than renumber the others, we made it freedom 0.</li> |
| 596 |
|
</ol> |
| 597 |
|
|
| 598 |
|
</div><!-- for id="content", starts in the include above --> |
| 599 |
|
<!--#include virtual="/server/footer.html" --> |
| 600 |
|
<div id="footer"> |
| 601 |
|
<div class="unprintable"> |
| 602 |
|
|
| 603 |
|
<p>Please send general FSF & GNU inquiries to |
| 604 |
|
<a href="mailto:gnu@gnu.org"><gnu@gnu.org></a>. |
| 605 |
|
There are also <a href="/contact/">other ways to contact</a> |
| 606 |
|
the FSF. Broken links and other corrections or suggestions can be sent |
| 607 |
|
to <a href="mailto:webmasters@gnu.org"><webmasters@gnu.org></a>.</p> |
| 608 |
|
|
| 609 |
|
<p><!-- TRANSLATORS: Ignore the original text in this paragraph, |
| 610 |
|
replace it with the translation of these two: |
| 611 |
|
|
| 612 |
|
We work hard and do our best to provide accurate, good quality |
| 613 |
|
translations. However, we are not exempt from imperfection. |
| 614 |
|
Please send your comments and general suggestions in this regard |
| 615 |
|
to <a href="mailto:web-translators@gnu.org"> |
| 616 |
|
<web-translators@gnu.org></a>.</p> |
| 617 |
|
|
| 618 |
|
<p>For information on coordinating and submitting translations of |
| 619 |
|
our web pages, see <a |
| 620 |
|
href="/server/standards/README.translations.html">Translations |
| 621 |
|
README</a>. --> |
| 622 |
|
Please see the <a |
| 623 |
|
href="/server/standards/README.translations.html">Translations |
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README</a> for information on coordinating and submitting translations |
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of this article.</p> |
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</div> |
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|
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<!-- Regarding copyright, in general, standalone pages (as opposed to |
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files generated as part of manuals) on the GNU web server should |
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be under CC BY-ND 4.0. Please do NOT change or remove this |
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without talking with the webmasters or licensing team first. |
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|
Please make sure the copyright date is consistent with the |
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document. For web pages, it is ok to list just the latest year the |
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|
document was modified, or published. |
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|
|
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If you wish to list earlier years, that is ok too. |
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Either "2001, 2002, 2003" or "2001-2003" are ok for specifying |
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years, as long as each year in the range is in fact a copyrightable |
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year, i.e., a year in which the document was published (including |
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being publicly visible on the web or in a revision control system). |
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|
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There is more detail about copyright years in the GNU Maintainers |
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Information document, www.gnu.org/prep/maintain. --> |
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|
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<p>Copyright © 1996, 2002, 2004-2007, 2009-2019 |
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Free Software Foundation, Inc.</p> |
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|
|
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<p>This page is licensed under a <a rel="license" |
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|
href="http://creativecommons.org/licenses/by-nd/4.0/">Creative |
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|
Commons Attribution-NoDerivatives 4.0 International License</a>.</p> |
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|
|
| 652 |
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<!--#include virtual="/server/bottom-notes.html" --> |
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|
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<p class="unprintable">Updated: |
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<!-- timestamp start --> |
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$Date$ |
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<!-- timestamp end --> |
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|
</p> |
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</div> |
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</div><!-- for class="inner", starts in the banner include --> |
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</body> |
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</html> |