++ ++The free software definition presents the criteria for whether a +particular software program qualifies as free software. From time to +time we revise this definition, to clarify it or to resolve questions +about subtle issues. See the History section +below for a list of changes that affect the definition of free +software. +
+
+“Free software” means software that respects users' +freedom and community. Roughly, the users have the freedom to run, +copy, distribute, study, change and improve the software. +
-We maintain this free software definition to show clearly what must -be true about a particular software program for it to be considered -free software. +Thus, “free software” is a matter of liberty, not price. +To understand the concept, you should think of “free” as +in “free speech,” not as in “free beer”.
-Free software
is a matter of liberty, not price. To understand
-the concept, you should think of free
as in free speech,
-not as in free beer.
+With these freedoms, the users (both individually and collectively)
+control the program and what it does for them. When users don't
+control the program, the program controls the users. The developer
+controls the program, and through it exercises power over the users.
+Therefore, a “nonfree” or “proprietary” program
+is an
+instrument of unjust power.
-Free software is a matter of the users' freedom to run, copy, distribute, -study, change and improve the software. More precisely, it refers to -four kinds of freedom, for the users of the software: +A program is free software if the program's users have the +four essential freedoms:
-A program is free software if users have all of these freedoms. Thus, -you should be free to redistribute copies, either with or without -modifications, either gratis or charging a fee for distribution, to +A program is free software if it gives users adequately all of these +freedoms. Otherwise, it is nonfree. While we can distinguish various +nonfree distribution schemes in terms of how far they fall short of +being free, we consider them all equally unethical.
+ +The rest of this page clarifies certain points about what makes +specific freedoms adequate or not.
+ +Freedom to distribute (freedoms 2 and 3) means you are free to +redistribute copies, either with or without modifications, either +gratis or charging a fee for distribution, to anyone anywhere. Being free to do these things means (among other things) that you do not have to ask or pay -for permission. +for permission to do so.
@@ -66,7 +97,7 @@ overall job and purpose, without being required to communicate about it with the developer or any other specific entity. In this freedom, it is the user's purpose that matters, not the developer's -purpose; you as a user are free to run a program for your purposes, +purpose; you as a user are free to run the program for your purposes, and if you distribute it to someone else, she is then free to run it for her purposes, but you are not entitled to impose your purposes on her.
@@ -75,7 +106,7 @@ The freedom to redistribute copies must include binary or executable forms of the program, as well as source code, for both modified and unmodified versions. (Distributing programs in runnable form is necessary -for conveniently installable free operating systems.) It is ok if there +for conveniently installable free operating systems.) It is OK if there is no way to produce a binary or executable form for a certain program (since some languages don't support that feature), but you must have the freedom to redistribute such forms should you find or develop a way to @@ -83,25 +114,49 @@-In order for the freedoms to make changes, and to publish improved -versions, to be meaningful, you must have access to the source code of -the program. Therefore, accessibility of source code is a necessary -condition for free software. +In order for freedoms 1 and 3 (the freedom to make changes and the +freedom to publish the changed versions) to be meaningful, you must have +access to the source code of the program. Therefore, accessibility of +source code is a necessary condition for free software. Obfuscated +“source code” is not real source code and does not count +as source code.
-One important way to modify a program is by merging in available -free subroutines and modules. If the program's license says that you -cannot merge in an existing module, such as if it requires you to be the -copyright holder of any code you add, then the license is too restrictive -to qualify as free. +Freedom 1 includes the freedom to use your changed version in place of +the original. If the program is delivered in a product designed to +run someone else's modified versions but refuse to run yours — a +practice known as “tivoization” or “lockdown”, +or (in its practitioners' perverse terminology) as “secure +boot” — freedom 1 becomes a theoretical fiction rather +than a practical freedom. This is not sufficient. In other words, +these binaries are not free software even if the source code they are +compiled from is free.
-In order for these freedoms to be real, they must be irrevocable as -long as you do nothing wrong; if the developer of the software has the -power to revoke the license, without your doing anything to give cause, -the software is not free. +One important way to modify a program is by merging in available free +subroutines and modules. If the program's license says that you +cannot merge in a suitably licensed existing module — for instance, if it +requires you to be the copyright holder of any code you add — then the +license is too restrictive to qualify as free. +
+ ++Freedom 3 includes the freedom to release your modified versions +as free software. A free license may also permit other ways of +releasing them; in other words, it does not have to be +a copyleft license. However, a +license that requires modified versions to be nonfree does not qualify +as a free license. +
+ ++In order for these freedoms to be real, they must be permanent and +irrevocable as long as you do nothing wrong; if the developer of the +software has the power to revoke the license, or retroactively add +restrictions to its terms, without your doing anything wrong to give +cause, the software is not free.
@@ -114,6 +169,10 @@
+“Free software” does not mean “noncommercial”. A free +program must be available for commercial use, commercial development, +and commercial distribution. Commercial development of free software +is no longer unusual; such free commercial software is very important. You may have paid money to get copies of free software, or you may have obtained copies at no charge. But regardless of how you got your copies, you always have the freedom to copy and change the software, even to @@ -121,41 +180,53 @@
-Free software
does not mean non-commercial.
A free
-program must be available for commercial use, commercial development,
-and commercial distribution. Commercial development of free software
-is no longer unusual; such free commercial software is very important.
+Whether a change constitutes an improvement is a subjective matter.
+If your right to modify a program is limited, in substance, to changes that
+someone else considers an improvement, that program is not free.
+
+However, rules about how to package a modified version are acceptable, +if they don't substantively limit your freedom to release modified +versions, or your freedom to make and use modified versions privately. +Thus, it is acceptable for the license to require that you change the +name of the modified version, remove a logo, or identify your +modifications as yours. As long as these requirements are not so +burdensome that they effectively hamper you from releasing your +changes, they are acceptable; you're already making other changes to +the program, so you won't have trouble making a few more.
-Rules about how to package a modified version are acceptable, if they
-don't substantively block your freedom to release modified versions, or
-your freedom to make and use modified versions privately. Rules that if
-you make your version 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 your version
-at all.) Rules that require release of source code to the users for
-versions that you put into public use are also acceptable. It is also
-acceptable for the license to require that, if you have distributed a
+Rules that “if you make your version available in this way, you
+must make it available in that way also” can be acceptable too,
+on the same condition. An example of such an acceptable rule is one
+saying 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.
+must send one. (Note that such a rule still leaves you the choice of
+whether to distribute your version at all.) Rules that require release
+of source code to the users for versions that you put into public use
+are also acceptable.
+A special issue arises when a license requires changing the name by +which the program will be invoked from other programs. That +effectively hampers you from releasing your changed version so that it +can replace the original when invoked by those other programs. This +sort of requirement is acceptable only if there's a suitable aliasing +facility that allows you to specify the original program's name as an +alias for the modified version.
+ +
In the GNU project, we use
-copyleft
+copyleft
to protect these freedoms legally for everyone. But
-non-copylefted
+noncopylefted
free software also exists. We believe there are important reasons why
- it is better to use copyleft,
-but if your program is non-copylefted free software, we can still
-use it.
-
-See Categories of Free Software
-for a description of how free software,
copylefted software
-and other categories of software relate to each other.
+it is better to use copyleft,
+but if your program is noncopylefted free software, it is still basically
+ethical. (See Categories of Free Software for a description of how “free software,” “copylefted software” and other categories of software relate to each other.)
@@ -165,7 +236,19 @@ 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. +jurisdictions of these governments. Thus, free software licenses +must not require obedience to any nontrivial export regulations as a +condition of exercising any of the essential freedoms. +
+ ++Merely mentioning the existence of export regulations, without making +them a condition of the license itself, is acceptable since it does +not restrict users. If an export regulation is actually trivial for +free software, then requiring it as a condition is not an actual +problem; however, it is a potential problem, since a later change in +export law could make the requirement nontrivial and thus render the +software nonfree.
@@ -176,7 +259,7 @@ (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. +such a license could be unacceptably restrictive and nonfree.
@@ -184,18 +267,18 @@ 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 conclude -it is non-free. +it is nonfree.
When talking about free software, it is best to avoid using terms
-like give away
or for free,
because those terms imply that
+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
+as “piracy” embody opinions we hope you won't endorse. See
Confusing Words and Phrases that
are Worth Avoiding for a discussion of these terms. We also have
-a list of translations of
-free software
into various languages.
+a list of proper translations of
+“free software” into various languages.
@@ -221,20 +304,20 @@
-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. +If you are contemplating writing a new license, please contact the +Free Software Foundation first 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.
If that isn't possible, if you really need a new license, with our -help you can ensure that the license really is a Free Software license +help you can ensure that the license really is a free software license and avoid various practical problems.
-Software manuals must be free, @@ -246,7 +329,7 @@ The same arguments also make sense for other kinds of works of practical use — that is to say, works that embody useful knowledge, such as educational works and reference -works. Wikipedia is the best known +works. Wikipedia is the best-known example.
@@ -256,151 +339,186 @@ free cultural works applicable to any kind of works. -
-Another group has started using the term open source
to mean
-something close (but not identical) to free software.
We
-prefer the term free software
because, once you have heard that
+Another group has started using the term “open source” to mean
+something close (but not identical) to “free software”. We
+prefer the term “free software” because, once you have heard that
it refers to freedom rather than price, it calls to mind freedom. The
-word open
+word “open”
never refers to freedom.
From time to time we revise this Free Software Definition. Here is +the list of substantive changes, along with links to show exactly what +was changed.
- +