License for your open-source project

    In this article I want to talk a bit about copyright and free software licenses. The text is the result of independent selection of licenses and their application to their projects.

    The article will be useful to those who want to:

    - In general terms, understand what copyright is (but it is better to contact a lawyer);
    - pick up a free license for your project;
    - figure out what needs to be written in the header of the source code file.

    The first thing is a link to LicenseIT , a very useful site with a description of licenses and the features of their application (including in Russia), which I managed not to find when preparing the article. Corrected. Thanks sensboston for the link.


    Copyright


    To begin with briefly about what copyright and licenses are in general.

    Meanwhile in Russia

    If you created a work (for example, a program) as the result of intellectual activity, then in this case you are its author (s). You have property and non-property rights to this work. You can transfer the property rights to this work to someone else, but you will not succeed in transferring the non-property, including authorship. Being an author is your inalienable and non-transferable right.

    Even if you worked "for uncle" when creating the work, then in this case the author is not at all some abstract LLC. Perhaps when you got a job, you also signed a clause on “alienation of exclusive rights to the results of your intellectual activity in favor of the employer” in the contract or something like that. Maybe not (in this case google "Official work "). In both cases, the author is you. And you have some rights.

    Licenses

    Another way to transfer rights to a work is through a license. In this case, the rights are not alienated, they are transferred in accordance with what is prescribed in the license agreement between the user and the copyright holder. Yes, a license is exactly a contract! All software licenses, both commercial and free, are such an agreement. It states what you can and cannot do with the software, and how far the copyright holder can send you in case of complaints. For example, a license may give you the right to install the program, but restrict this right to only one computer , otherwise uncle masks will come to you and take everything away .

    Pay attention to an important point: if you have enough rights to a work, then you can distribute it under different licenses (including at the same time). For example, on your site you can distribute the program for free under a free license, and in any application store it can be sold for money under their standard license.

    You can also change the license at any time: for example, today the program on your site was free under a free license, and tomorrow it is paid and with closed sources. But in this case, you cannot force users who downloaded the program earlier to follow the rules of the new license. This is logical, because they received the program under another contract.

    In the world

    In general, the above applies to most countries of the world. The fact is that thanks to several international conventions, copyright laws in the world are similar (but there are also a number of countries that have not signed the conventions). However, even so, differences exist. For example, in Russia non-property rights are not alienated. And, say, in Canada you can refuse them, but you can’t pass them on. Therefore, if possible, it is best to always consult a local lawyer.

    Free licenses


    Define the definition

    To search for a definition, I will send those who wish to Wikipedia , for which I will give links to several articles at once:

    This is not because I am so angry (although I really do not have a bicycle), but because there is no clear definition for the term free license. From these articles, one can deduce approximately the following: A

    free license is a license that meets certain criteria of free software. Usually, they use either the free software definition given by Richard Stallman or the Debian free software criteria formulated by Bruce Perens . Accordingly, those licenses that are not free are not free.

    In my personal opinion, there is no point in bothering with specific definitions, we are not politicians (well, at least I am). But from a practical point of view, the main difference between free and non-free licenses is for purposes. Non-free licenses are used for the purpose of making money and not allowing competitors to make money on it, free licenses are used to provide an opportunity to use the fruits of your labor for free.

    Copyleft

    Before proceeding with the description of licenses, you need to understand what copyleft and permissive (permissive) licenses are. Free licenses are considered copyleft, requiring the distribution of derivative products under the same license. That is, if you used a library under your copyleft license in your program, then you will have to distribute your program under it. The task of permits, on the contrary, is to allow any possible use of the product.

    Basic free licenses

    A large list of free licenses can be found on the GNU website .
    Also, sensboston provided a link to another list with open-source licenses .
    Here I will give a list of licenses, in which there will be those licenses that I consider the most useful and / or significant, and those about which you suggested writing in the comments.

    GPLv3 (GNU General Public License Version 3)
    License Text
                        GNU GENERAL PUBLIC LICENSE
                           Version 3, 29 June 2007
     Copyright (C) 2007 Free Software Foundation, Inc. 
     Everyone is permitted to copy and distribute verbatim copies
     of this license document, but changing it is not allowed.
                                Preamble
      The GNU General Public License is a free, copyleft license for
    software and other kinds of works.
      The licenses for most software and other practical works are designed
    to take away your freedom to share and change the works. By contrast,
    the GNU General Public License is intended to guarantee your freedom to
    share and change all versions of a program - to make sure it remains free
    software for all its users. We, the Free Software Foundation, use the
    GNU General Public License for most of our software; it applies also to
    any other work released this way by its authors. You can apply it to
    your programs, too.
      When we speak of free software, we are referring to freedom, not
    price. Our General Public Licenses are designed to make sure that you
    have the freedom to distribute copies of free software (and charge for
    them if you wish), that you receive source code or can get it if you
    want it, that you can change the software or use pieces of it in new
    free programs, and that you know you can do these things.
      To protect your rights, we need to prevent others from denying you
    these rights or asking you to surrender the rights. Therefore, you have
    certain responsibilities if you distribute copies of the software, or if
    you modify it: responsibilities to respect the freedom of others.
      For example, if you distribute copies of such a program, whether
    gratis or for a fee, you must pass on to the recipients the same
    freedoms that you received. You must make sure that they, too, receive
    or can get the source code. And you must show them these terms so they
    know their rights.
      Developers that use the GNU GPL protect your rights with two steps:
    (1) assert copyright on the software, and (2) offer you this License
    giving you legal permission to copy, distribute and / or modify it.
      For the developers 'and authors' protection, the GPL clearly explains
    that there is no warranty for this free software. For both users' and
    authors' sake, the GPL requires that modified versions be marked as
    changed, so that their problems will not be attributed erroneously to
    authors of previous versions.
      Some devices are designed to deny users access to install or run
    modified versions of the software inside them, although the manufacturer
    can do so. This is fundamentally incompatible with the aim of
    protecting users' freedom to change the software. The systematic
    pattern of such abuse occurs in the area of ​​products for individuals to
    use, which is precisely where it is most unacceptable. Therefore, we
    have designed this version of the GPL to prohibit the practice for those
    products. If such problems arise substantially in other domains, we
    stand ready to extend this provision to those domains in future versions
    of the GPL, as needed to protect the freedom of users.
      Finally, every program is threatened constantly by software patents.
    States should not allow patents to restrict development and use of
    software on general-purpose computers, but in those that do, we wish to
    avoid the special danger that patents applied to a free program could
    make it effectively proprietary. To prevent this, the GPL assures that
    patents cannot be used to render the program non-free.
      The precise terms and conditions for copying, distribution and
    modification follow.
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    permission to link or combine any covered work with a work licensed
    under version 3 of the GNU Affero General Public License into a single
    combined work, and to convey the resulting work. The terms of this
    License will continue to apply to the part which is the covered work,
    but the special requirements of the GNU Affero General Public License,
    section 13, concerning interaction through a network will apply to the
    combination as such.
      14. Revised Versions of this License.
      The Free Software Foundation may publish revised and / or new versions of
    the GNU General Public License from time to time. Such new versions will
    be similar in spirit to the present version, but may differ in detail to
    address new problems or concerns.
      Each version is given a distinguishing version number. If the
    Program specifies that a certain numbered version of the GNU General
    Public License "or any later version" applies to it, you have the
    option of following the terms and conditions either of that numbered
    version or of any later version published by the Free Software
    Foundation. If the Program does not specify a version number of the
    GNU General Public License, you may choose any version ever published
    by the Free Software Foundation.
      If the Program specifies that a proxy can decide which future
    versions of the GNU General Public License can be used, that proxy's
    public statement of acceptance of a version permanently authorizes you
    to choose that version for the Program.
      Later license versions may give you additional or different
    permissions. However, no additional obligations are imposed on any
    author or copyright holder as a result of your choosing to follow a
    later version.
      15. Disclaimer of Warranty.
      THERE IS NO WARRANTY FOR THE PROGRAM, TO THE EXTENT PERMITTED BY
    APPLICABLE LAW. EXCEPT WHEN OTHERWISE STATED IN WRITING THE COPYRIGHT
    HOLDERS AND / OR OTHER PARTIES PROVIDE THE PROGRAM "AS IS" WITHOUT WARRANTY
    OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING, BUT NOT LIMITED TO,
    THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
    PURPOSE. THE ENTIRE RISK AS TO THE QUALITY AND PERFORMANCE OF THE PROGRAM
    IS WITH YOU. SHOULD THE PROGRAM PROVE DEFECTIVE, YOU ASSUME THE COST OF
    ALL NECESSARY SERVICING, REPAIR OR CORRECTION.
      16. Limitation of Liability.
      IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING
    WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MODIFIES AND / OR CONVEYS
    THE PROGRAM AS PERMITTED ABOVE, BE LIABLE TO YOU FOR DAMAGES, INCLUDING ANY
    GENERAL, SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF THE
    USE OR INABILITY TO USE THE PROGRAM (INCLUDING BUT NOT LIMITED TO LOSS OF
    DATA OR DATA BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY YOU OR THIRD
    PARTIES OR A FAILURE OF THE PROGRAM TO OPERATE WITH ANY OTHER PROGRAMS),
    EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE POSSIBILITY OF
    SUCH DAMAGES.
      17. Interpretation of Sections 15 and 16.
      If the disclaimer of warranty and limitation of liability provided
    above cannot be given local legal effect according to their terms,
    reviewing courts shall apply local law that most closely approximates
    an absolute waiver of all civil liability in connection with the
    Program, unless a warranty or assumption of liability accompanies a
    copy of the Program in return for a fee.
                         END OF TERMS AND CONDITIONS
                How to Apply These Terms to Your New Programs
      If you develop a new program, and you want it to be of the greatest
    possible use to the public, the best way to achieve this is to make it
    free software which everyone can redistribute and change under these terms.
      To do so, attach the following notices to the program. It is safest
    to attach them to the start of each source file to most effectively
    state the exclusion of warranty; and each file should have at least
    the "copyright" line and a pointer to where the full notice is found.
        
        Copyright (C) 
        This program is free software: you can redistribute it and / or modify
        it under the terms of the GNU General Public License as published by
        the Free Software Foundation, either version 3 of the License, or
        (at your option) any later version.
        This program is distributed in the hope that it will be useful,
        but WITHOUT ANY WARRANTY; without even the implied warranty of
        MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
        GNU General Public License for more details.
        You should have received a copy of the GNU General Public License
        along with this program. If not, see.
    Also add information on how to contact you by electronic and paper mail.
      If the program does terminal interaction, make it output a short
    notice like this when it starts in an interactive mode:
          Copyright (C) 
        This program comes with ABSOLUTELY NO WARRANTY; for details type `show w '.
        This is free software, and you are welcome to redistribute it
        under certain conditions; type `show c 'for details.
    The hypothetical commands `show w 'and` show c' should show the appropriate
    parts of the General Public License. Of course, your program's commands
    might be different; for a GUI interface, you would use an "about box".
      You should also get your employer (if you work as a programmer) or school,
    if any, to sign a "copyright disclaimer" for the program, if necessary.
    For more information on this, and how to apply and follow the GNU GPL, see
    .
      The GNU General Public License does not permit incorporating your program
    into proprietary programs. If your program is a subroutine library, you
    may consider it more useful to permit linking proprietary applications with
    the library. If this is what you want to do, use the GNU Lesser General
    Public License instead of this License. But first, please read
    .
    How to Apply GNU Licenses with Your Programs
    GPL Compliance Practical Guide , thanks Indexator for the link.
    GNU GPL 3 in human language , thanks again Indexator .
    The most famous of the free licenses. Not in the sense that everyone understands her well, but in the fact that she is most heard. Since it is called free, many mistakenly believe that code released under the GPL can be used as you like, and programs can / should only be free. Both that, and another - a lie. The GNU GPL is a copyleft license, and requires that the source codes of derivative works be open under it. That is, if you decide to use the library under the GPL in your project,you will have to lay out the source code of your project under the GPL, which is usually unacceptable for commercial development; you will have to provide the source code for the project to the final recipients free of charge, even if you distribute the product for money (thanks to the coh habrayuzer for pointing out inaccuracies). Yes, selling the program with a license is fully permitted. You can provide source codes both with the program and separately. In the second case, the binary version of the program should contain clear instructions for obtaining the source codes. A more detailed explanation is the translation of part of the official GPL FAQ (thanks again, coh !).

    GPLv2 (GNU General Public License Version 2)
    License Text
                        GNU GENERAL PUBLIC LICENSE
                           Version 2, June 1991
     Copyright (C) 1989, 1991 Free Software Foundation, Inc.,
     51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
     Everyone is permitted to copy and distribute verbatim copies
     of this license document, but changing it is not allowed.
                                Preamble
      The licenses for most software are designed to take away your
    freedom to share and change it. By contrast, the GNU General Public
    License is intended to guarantee your freedom to share and change free
    software - to make sure the software is free for all its users. This
    General Public License applies to most of the Free Software
    Foundation's software and to any other program whose authors commit to
    using it. (Some other Free Software Foundation software is covered by
    the GNU Lesser General Public License instead.) You can apply it to
    your programs, too.
      When we speak of free software, we are referring to freedom, not
    price. Our General Public Licenses are designed to make sure that you
    have the freedom to distribute copies of free software (and charge for
    this service if you wish), that you receive source code or can get it
    if you want it, that you can change the software or use pieces of it
    in new free programs; and that you know you can do these things.
      To protect your rights, we need to make restrictions that forbid
    anyone to deny you these rights or to ask you to surrender the rights.
    These restrictions translate to certain responsibilities for you if you
    distribute copies of the software, or if you modify it.
      For example, if you distribute copies of such a program, whether
    gratis or for a fee, you must give the recipients all the rights that
    you have. You must make sure that they, too, receive or can get the
    source code. And you must show them these terms so they know their
    rights.
      We protect your rights with two steps: (1) copyright the software, and
    (2) offer you this license which gives you legal permission to copy,
    distribute and / or modify the software.
      Also, for each author's protection and ours, we want to make certain
    that everyone understands that there is no warranty for this free
    software. If the software is modified by someone else and passed on, we
    want its recipients to know that what they have is not the original, so
    that any problems introduced by others will not reflect on the original
    authors' reputations.
      Finally, any free program is threatened constantly by software
    patents. We wish to avoid the danger that redistributors of a free
    program will individually obtain patent licenses, in effect making the
    program proprietary. To prevent this, we have made it clear that any
    patent must be licensed for everyone's free use or not licensed at all.
      The precise terms and conditions for copying, distribution and
    modification follow.
                        GNU GENERAL PUBLIC LICENSE
       TERMS AND CONDITIONS FOR COPYING, DISTRIBUTION AND MODIFICATION
      0. This License applies to any program or other work which contains
    a notice placed by the copyright holder saying it may be distributed
    under the terms of this General Public License. The "Program", below,
    refers to any such program or work, and a "work based on the Program"
    means either the Program or any derivative work under copyright law:
    that is to say, a work containing the Program or a portion of it,
    either verbatim or with modifications and / or translated into another
    language. (Hereinafter, translation is included without limitation in
    the term "modification".) Each licensee is addressed as "you".
    Activities other than copying, distribution and modification are not
    covered by this License; they are outside its scope. The act of
    running the Program is not restricted, and the output from the Program
    is covered only if its contents constitute a work based on the
    Program (independent of having been made by running the Program).
    Whether that is true depends on what the Program does.
      1. You may copy and distribute verbatim copies of the Program's
    source code as you receive it, in any medium, provided that you
    conspicuously and appropriately publish on each copy an appropriate
    copyright notice and disclaimer of warranty; keep intact all the
    notices that refer to this License and to the absence of any warranty;
    and give any other recipients of the Program a copy of this License
    along with the Program.
    You may charge a fee for the physical act of transferring a copy, and
    you may at your option offer warranty protection in exchange for a fee.
      2. You may modify your copy or copies of the Program or any portion
    of it, thus forming a work based on the Program, and copy and
    distribute such modifications or work under the terms of Section 1
    above, provided that you also meet all of these conditions:
        a) You must cause the modified files to carry prominent notices
        stating that you changed the files and the date of any change.
        b) You must cause any work that you distribute or publish, that in
        whole or in part contains or is derived from the Program or any
        part thereof, to be licensed as a whole at no charge to all third
        parties under the terms of this License.
        c) If the modified program normally reads commands interactively
        when run, you must cause it, when started running for such
        interactive use in the most ordinary way, to print or display an
        announcement including an appropriate copyright notice and a
        notice that there is no warranty (or else, saying that you provide
        a warranty) and that users may redistribute the program under
        these conditions, and telling the user how to view a copy of this
        License. (Exception: if the Program itself is interactive but
        does not normally print such an announcement, your work based on
        the Program is not required to print an announcement.)
    These requirements apply to the modified work as a whole. If
    identifiable sections of that work are not derived from the Program,
    and can be reasonably considered independent and separate works in
    themselves, then this License, and its terms, do not apply to those
    sections when you distribute them as separate works. But when you
    distribute the same sections as part of a whole which is a work based
    on the Program, the distribution of the whole must be on the terms of
    this License, whose permissions for other licensees extend to the
    entire whole, and thus to each and every part regardless of who wrote it.
    Thus, it is not the intent of this section to claim rights or contest
    your rights to work written entirely by you; rather, the intent is to
    exercise the right to control the distribution of derivative or
    collective works based on the Program.
    In addition, mere aggregation of another work not based on the Program
    with the Program (or with a work based on the Program) on a volume of
    a storage or distribution medium does not bring the other work under
    the scope of this License.
      3. You may copy and distribute the Program (or a work based on it,
    under Section 2) in object code or executable form under the terms of
    Sections 1 and 2 above provided that you also do one of the following:
        a) Accompany it with the complete corresponding machine-readable
        source code, which must be distributed under the terms of Sections
        1 and 2 above on a medium customarily used for software interchange; or,
        b) Accompany it with a written offer, valid for at least three
        years, to give any third party, for a charge no more than your
        cost of physically performing source distribution, a complete
        machine-readable copy of the corresponding source code, to be
        distributed under the terms of Sections 1 and 2 above on a medium
        customarily used for software interchange; or,
        c) Accompany it with the information you received as to the offer
        to distribute corresponding source code. (This alternative is
        allowed only for noncommercial distribution and only if you
        received the program in object code or executable form with such
        an offer, in accord with Subsection b above.)
    The source code for a work means the preferred form of the work for
    making modifications to it. For an executable work, complete source
    code means all the source code for all modules it contains, plus any
    associated interface definition files, plus the scripts used to
    control compilation and installation of the executable. However, as a
    special exception, the source code distributed need not include
    anything that is normally distributed (in either source or binary
    form) with the major components (compiler, kernel, and so on) of the
    operating system on which the executable runs, unless that component
    itself accompanies the executable.
    If distribution of executable or object code is made by offering
    access to copy from a designated place, then offering equivalent
    access to copy the source code from the same place counts as
    distribution of the source code, even though third parties are not
    compelled to copy the source along with the object code.
      4. You may not copy, modify, sublicense, or distribute the Program
    except as expressly provided under this License. Any attempt
    otherwise to copy, modify, sublicense or distribute the Program is
    void, and will automatically terminate your rights under this License.
    However, parties who have received copies, or rights, from you under
    this License will not have their licenses terminated so long as such
    parties remain in full compliance.
      5. You are not required to accept this License, since you have not
    signed it. However, nothing else grants you permission to modify or
    distribute the Program or its derivative works. These actions are
    prohibited by law if you do not accept this License. Therefore, by
    modifying or distributing the Program (or any work based on the
    Program), you indicate your acceptance of this License to do so, and
    all its terms and conditions for copying, distributing or modifying
    the Program or works based on it.
      6. Each time you redistribute the Program (or any work based on the
    Program), the recipient automatically receives a license from the
    original licensor to copy, distribute or modify the Program subject to
    these terms and conditions. You may not impose any further
    restrictions on the recipients' exercise of the rights granted listed.
    You are not responsible for enforcing compliance by third parties to
    this License.
      7. If, as a consequence of a court judgment or allegation of patent
    infringement or for any other reason (not limited to patent issues),
    conditions are imposed on you (whether by court order, agreement or
    otherwise) that contradict the conditions of this License, they do not
    excuse you from the conditions of this License. If you cannot
    distribute so as to satisfy simultaneously your obligations under this
    License and any other pertinent obligations, then as a consequence you
    may not distribute the Program at all. For example, if a patent
    license would not permit royalty-free redistribution of the Program by
    all those who receive copies directly or indirectly through you, then
    the only way you could satisfy both it and this License would be to
    refrain entirely from distribution of the Program.
    If any portion of this section is held invalid or unenforceable under
    any particular circumstance, the balance of the section is intended to
    apply and the section as a whole is intended to apply in other
    circumstances.
    It is not the purpose of this section to induce you to infringe any
    patents or other property right claims or to contest validity of any
    such claims; this section has the sole purpose of protecting the
    integrity of the free software distribution system, which is
    implemented by public license practices. Many people have made
    generous contributions to the wide range of software distributed
    through that system in reliance on consistent application of that
    system; it is up to the author / donor to decide if he or she is willing
    to distribute software through any other system and a licensee cannot
    impose that choice.
    This section is intended to make thoroughly clear what is believed to
    be a consequence of the rest of this License.
      8. If the distribution and / or use of the Program is restricted in
    certain countries either by patents or by copyrighted interfaces, the
    original copyright holder who places the Program under this License
    may add an explicit geographical distribution limitation excluding
    those countries, so that distribution is permitted only in or among
    countries not thus excluded. In such case, this License incorporates
    the limitation as if written in the body of this License.
      9. The Free Software Foundation may publish revised and / or new versions
    of the General Public License from time to time. Such new versions will
    be similar in spirit to the present version, but may differ in detail to
    address new problems or concerns.
    Each version is given a distinguishing version number. If the program
    specifies a version number of this License which applies to it and "any
    later version ", you have the option of following the terms and conditions
    either of that version or of any later version published by the Free
    Software Foundation. If the Program does not specify a version number of
    this License, you may choose any version ever published by the Free Software
    Foundation.
      10. If you wish to incorporate parts of the Program into other free
    programs whose distribution conditions are different, write to the author
    to ask for permission. For software which is copyrighted by the Free
    Software Foundation, write to the Free Software Foundation; we sometimes
    make exceptions for this. Our decision will be guided by the two goals
    of preserving the free status of all derivatives of our free software and
    of promoting the sharing and reuse of software generally.
                                NO WARRANTY
      11. BECAUSE THE PROGRAM IS LICENSED FREE OF CHARGE, THERE IS NO WARRANTY
    FOR THE PROGRAM, TO THE EXTENT PERMITTED BY APPLICABLE LAW. EXCEPT WHEN
    OTHERWISE STATED IN WRITING THE COPYRIGHT HOLDERS AND / OR OTHER PARTIES
    PROVIDE THE PROGRAM "AS IS" WITHOUT WARRANTY OF ANY KIND, EITHER EXPRESSED
    OR IMPLIED, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
    MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. THE ENTIRE RISK AS
    TO THE QUALITY AND PERFORMANCE OF THE PROGRAM IS WITH YOU. SHOULD THE
    PROGRAM PROVE DEFECTIVE, YOU ASSUME THE COST OF ALL NECESSARY SERVICING,
    REPAIR OR CORRECTION.
      12. IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING
    WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MAY MODIFY AND / OR
    REDISTRIBUTE THE PROGRAM AS PERMITTED ABOVE, BE LIABLE TO YOU FOR DAMAGES,
    INCLUDING ANY GENERAL, SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING
    OUT OF THE USE OR INABILITY TO USE THE PROGRAM (INCLUDING BUT NOT LIMITED
    TO LOSS OF DATA OR DATA BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY
    YOU OR THIRD PARTIES OR A FAILURE OF THE PROGRAM TO OPERATE WITH ANY OTHER
    PROGRAMS), EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE
    POSSIBILITY OF SUCH DAMAGES.
                         END OF TERMS AND CONDITIONS
                How to Apply These Terms to Your New Programs
      If you develop a new program, and you want it to be of the greatest
    possible use to the public, the best way to achieve this is to make it
    free software which everyone can redistribute and change under these terms.
      To do so, attach the following notices to the program. It is safest
    to attach them to the start of each source file to most effectively
    convey the exclusion of warranty; and each file should have at least
    the "copyright" line and a pointer to where the full notice is found.
        
        Copyright (C) 
        This program is free software; you can redistribute it and / or modify
        it under the terms of the GNU General Public License as published by
        the Free Software Foundation; either version 2 of the License, or
        (at your option) any later version.
        This program is distributed in the hope that it will be useful,
        but WITHOUT ANY WARRANTY; without even the implied warranty of
        MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
        GNU General Public License for more details.
        You should have received a copy of the GNU General Public License along
        with this program; if not, write to the Free Software Foundation, Inc.,
        51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
    Also add information on how to contact you by electronic and paper mail.
    If the program is interactive, make it output a short notice like this
    when it starts in an interactive mode:
        Gnomovision version 69, Copyright (C) year name of author
        Gnomovision comes with ABSOLUTELY NO WARRANTY; for details type `show w '.
        This is free software, and you are welcome to redistribute it
        under certain conditions; type `show c 'for details.
    The hypothetical commands `show w 'and` show c' should show the appropriate
    parts of the General Public License. Of course, the commands you use may
    be called something other than `show w 'and` show c'; they could even be
    mouse-clicks or menu items - whatever suits your program.
    You should also get your employer (if you work as a programmer) or your
    school, if any, to sign a "copyright disclaimer" for the program, if
    necessary. Here is a sample; alter the names:
      Yoyodyne, Inc., hereby disclaims all copyright interest in the program
      `Gnomovision '(which makes passes at compilers) written by James Hacker.
      April 1, 1989
      Ty Coon, President of Vice
    This General Public License does not permit incorporating your program into
    proprietary programs. If your program is a subroutine library, you may
    consider it more useful to permit linking proprietary applications with the
    library. If this is what you want to do, use the GNU Lesser General
    Public License instead of this License.
    How to Apply GNU Licenses with Your Programs
    GPL Compliance Practical Guide , thanks Indexator for the link.
    As reasonably pointed out by wholeman in the comments, the description of the GNU GPL version 2 is not enough. The differences between the two versions of the GPL can be read, for example, in this article . Also, from wholeman's comment :
    GPLv3 is noticeably stricter and may cause some problems for the author. For example, one of the requirements is that instructions should be provided for installing the modified application on the device. For applications under iOS or WindowsPhone, where there is no regular ability to install the package from outside the store, fulfilling this requirement is problematic.
    In addition, it is worth noting that most of the programs released under the GNU GPLv2 allow the use under a later version of the license.

    And, just in case: the GNU license compatibility table .

    LGPLv3 (GNU Lesser General Public License Version 3, nee GNU Library General Public License)
    License Text
                       GNU LESSER GENERAL PUBLIC LICENSE
                           Version 3, 29 June 2007
     Copyright (C) 2007 Free Software Foundation, Inc. 
     Everyone is permitted to copy and distribute verbatim copies
     of this license document, but changing it is not allowed.
      This version of the GNU Lesser General Public License incorporates
    the terms and conditions of version 3 of the GNU General Public
    License, supplemented by the additional permissions listed below.
      0. Additional Definitions.
      As used List, "this License" refers to version 3 of the GNU Lesser
    General Public License, and the "GNU GPL" refers to version 3 of the GNU
    General Public License.
      "The Library" refers to a covered work governed by this License,
    other than an Application or a Combined Work as defined below.
      An "Application" is any work that makes use of an interface provided
    by the Library, but which is not otherwise based on the Library.
    Defining a subclass of a class defined by the Library is deemed a mode
    of using an interface provided by the Library.
      A "Combined Work" is a work produced by combining or linking an
    Application with the Library. The particular version of the Library
    with which the Combined Work was made is also called the "Linked
    Version ".
      The "Minimal Corresponding Source" for a Combined Work means the
    Corresponding Source for the Combined Work, excluding any source code
    for portions of the Combined Work that, considered in isolation, are
    based on the Application, and not on the Linked Version.
      The "Corresponding Application Code" for a Combined Work means the
    object code and / or source code for the Application, including any data
    and utility programs needed for reproducing the Combined Work from the
    Application, but excluding the System Libraries of the Combined Work.
      1. Exception to Section 3 of the GNU GPL.
      You may convey a covered work under sections 3 and 4 of this License
    without being bound by section 3 of the GNU GPL.
      2. Conveying Modified Versions.
      If you modify a copy of the Library, and, in your modifications, a
    facility refers to a function or data to be supplied by an Application
    that uses the facility (other than as an argument passed when the
    facility is invoked), then you may convey a copy of the modified
    version:
       a) under this License, provided that you make a good faith effort to
       ensure that, in the event an Application does not supply the
       function or data, the facility still operates, and performs
       whatever part of its purpose remains meaningful, or
       b) under the GNU GPL, with none of the additional permissions of
       this License applicable to that copy.
      3. Object Code Incorporating Material from Library Header Files.
      The object code form of an application may incorporate material from
    a header file that is part of the Library. You may convey such object
    code under terms of your choice, provided that, if the incorporated
    material is not limited to numerical parameters, data structure
    layouts and accessors, or small macros, inline functions and templates
    (ten or fewer lines in length), you do both of the following:
       a) Give prominent notice with each copy of the object code that the
       Library is used in it and that the Library and its use are
       covered by this License.
       b) Accompany the object code with a copy of the GNU GPL and this license
       document.
      4. Combined Works.
      You may convey a Combined Work under terms of your choice that,
    taken together, effectively do not restrict modification of the
    portions of the Library contained in the Combined Work and reverse
    engineering for debugging such modifications, if you also do each of
    the following:
       a) Give prominent notice with each copy of the Combined Work that
       the Library is used in it and that the Library and its use are
       covered by this License.
       b) Accompany the Combined Work with a copy of the GNU GPL and this license
       document.
       c) For a Combined Work that displays copyright notices during
       execution, include the copyright notice for the Library among
       these notices, as well as a reference directing the user to the
       copies of the GNU GPL and this license document.
       d) Do one of the following:
           0) Convey the Minimal Corresponding Source under the terms of this
           License, and the Corresponding Application Code in a form
           suitable for, and under terms that permit, the user to
           recombine or relink the Application with a modified version of
           the Linked Version to produce a modified Combined Work, in the
           manner specified by section 6 of the GNU GPL for conveying
           Corresponding Source.
           1) Use a suitable shared library mechanism for linking with the
           Library A suitable mechanism is one that (a) uses at run time
           a copy of the Library already present on the user's computer
           system, and (b) will operate properly with a modified version
           of the Library that is interface-compatible with the Linked
           Version.
       e) Provide Installation Information, but only if you would otherwise
       be required to provide such information under section 6 of the
       GNU GPL, and only to the extent that such information is
       necessary to install and execute a modified version of the
       Combined Work produced by recombining or relinking the
       Application with a modified version of the Linked Version. (If
       you use option 4d0, the Installation Information must accompany
       the Minimal Corresponding Source and Corresponding Application
       Code If you use option 4d1, you must provide the Installation
       Information in the manner specified by section 6 of the GNU GPL
       for conveying Corresponding Source.)
      5. Combined Libraries.
      You may place library facilities that are a work based on the
    Library side by side in a single library together with other library
    facilities that are not Applications and are not covered by this
    License, and convey such a combined library under terms of your
    choice, if you do both of the following:
       a) Accompany the combined library with a copy of the same work based
       on the Library, uncombined with any other library facilities,
       conveyed under the terms of this License.
       b) Give prominent notice with the combined library that part of it
       is a work based on the Library, and explaining where to find the
       accompanying uncombined form of the same work.
      6. Revised Versions of the GNU Lesser General Public License.
      The Free Software Foundation may publish revised and / or new versions
    of the GNU Lesser General Public License from time to time. Such new
    versions will be similar in spirit to the present version, but may
    differ in detail to address new problems or concerns.
      Each version is given a distinguishing version number. If the
    Library as you received it specifies that a certain numbered version
    of the GNU Lesser General Public License "or any later version"
    applies to it, you have the option of following the terms and
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    copy of the Program in return for a fee.
                         END OF TERMS AND CONDITIONS
                How to Apply These Terms to Your New Programs
      If you develop a new program, and you want it to be of the greatest
    possible use to the public, the best way to achieve this is to make it
    free software which everyone can redistribute and change under these terms.
      To do so, attach the following notices to the program. It is safest
    to attach them to the start of each source file to most effectively
    state the exclusion of warranty; and each file should have at least
    the "copyright" line and a pointer to where the full notice is found.
        
        Copyright (C) 
        This program is free software: you can redistribute it and / or modify
        it under the terms of the GNU Affero General Public License as published by
        the Free Software Foundation, either version 3 of the License, or
        (at your option) any later version.
        This program is distributed in the hope that it will be useful,
        but WITHOUT ANY WARRANTY; without even the implied warranty of
        MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
        GNU Affero General Public License for more details.
        You should have received a copy of the GNU Affero General Public License
        along with this program.  If not, see .
    Also add information on how to contact you by electronic and paper mail.
      If your software can interact with users remotely through a computer
    network, you should also make sure that it provides a way for users to
    get its source.  For example, if your program is a web application, its
    interface could display a "Source" link that leads users to an archive
    of the code. There are many ways you could offer source, and different
    solutions will be better for different programs; see section 13 for the
    specific requirements.
      You should also get your employer (if you work as a programmer) or school,
    if any, to sign a "copyright disclaimer" for the program, if necessary.
    For more information on this, and how to apply and follow the GNU AGPL, see
    .
    How to apply GNU licenses with your programs
    Thanks to coh and lorus for remembering it. This is a copyleft license.

    Quoting Various licenses and comments on them :
    Its conditions actually consist of the GPLv3 conditions with an additional paragraph in section 13, which allows users interacting with the licensed program over the network to obtain the source code of this program. We encourage developers to consider using GNU AGPL for any programs that typically run on the network.
    There are certain nuances of compatibility with other versions of the GPL:
    Please note that GNU AGPL is not compatible with GPLv2. It is also formally incompatible with GPLv3 in the narrow sense: you cannot take source codes released under the GNU AGPL terms and transmit or modify them, as you wish, under the terms of GPLv3, and vice versa. However, you are allowed to combine separate modules or source files released under both of these licenses in a single project, which will give many programmers permission for all the actions they need in order to do whatever programs they like.

    MPL v2.0 (Mozilla Public License
    Version 2.0)
    License Text
    Mozilla Public License
    Version 2.0
    1. Definitions
    1.1. “Contributor”
        means each individual or legal entity that creates, contributes to
    the creation of, or owns Covered Software. 1.2. “Contributor Version”
        means the combination of the Contributions of others (if any) used
    by a Contributor and that particular Contributor's Contribution.
    1.3. “Contribution”
        means Covered Software of a particular Contributor. 1.4. “Covered
    Software ”
        means Source Code Form to which the initial Contributor has
    attached the notice in Exhibit A, the Executable Form of such Source
    Code Form, and Modifications of such Source Code Form, in each case
    including portions therefore. 1.5. “Incompatible With Secondary
    Licenses ”
        means
            that the initial Contributor has attached the notice described
            in Exhibit B to the Covered Software; or
            that the Covered Software was made available under the terms
            of version 1.1 or earlier of the License, but not also under
            the terms of a Secondary License.
    1.6. “Executable Form”
        means any form of the work other than Source Code Form.
    1.7. “Larger Work”
        means a work that combines Covered Software with other material,
    in a separate file or files, that is not Covered Software.
    1.8. “License”
        means this document.
    1.9. “Licensable”
        means having the right to grant, to the maximum extent possible,
    whether at the time of the initial grant or subsequently, any and all
    of the rights conveyed by this License. 1.10. “Modifications”
        means any of the following:
            any file in Source Code Form that results from an addition to,
            deletion from, or modification of the contents of Covered
            Software or
            any new file in Source Code Form that contains any Covered Software.
    1.11. “Patent Claims” of a Contributor
        means any patent claim (s), including without limitation, method,
    process, and apparatus claims, in any patent Licensable by such
    Contributor that would be infringed, but for the grant of the License,
    by the making, using, selling, offering for sale, having made, import,
    or transfer of either its Contributions or its Contributor Version.
    1.12. “Secondary License”
        means either the GNU General Public License, Version 2.0, the GNU
    Lesser General Public License, Version 2.1, the GNU Affero General
    Public License, Version 3.0, or any later versions of those licenses.
    1.13. “Source Code Form”
        means the form of the work preferred for making modifications.
    1.14. “You” (or “Your”)
        means an individual or a legal entity exercising rights under this
        License. For legal entities, “You” includes any entity that
        controls, is controlled by, or is under common control with
        You. For purposes of this definition, “control” means (a) the
        power, direct or indirect, to cause the direction or management of
        such entity, whether by contract or otherwise, or (b) ownership of
        more than fifty percent (50%) of the outstanding shares or
        beneficial ownership of such entity.
    2. License Grants and Conditions
    2.1. Grants
    Each Contributor hereby grants You a world-wide, royalty-free,
    non-exclusive license:
        under intellectual property rights (other than patent or
        trademark) Licensable by such Contributor to use, reproduce, make
        available, modify, display, perform, distribute, and otherwise
        exploit its Contributions, either on an unmodified basis, with
        Modifications, or as part of a Larger Work; and
        under Patent Claims of such Contributor to make, use, sell, offer
        for sale, have made, import, and otherwise transfer either its
        Contributions or its Contributor Version.
    2.2. Effective Date
    The licenses granted in Section 2.1 with respect to any Contribution
    become effective for each Contribution on the date the Contributor
    first distributes such Contribution. 2.3. Limitations on grant scope
    The licenses granted in this Section 2 are the only rights granted
    under this License. No additional rights or licenses will be implied
    from the distribution or licensing of Covered Software under this
    License. Notwithstanding Section 2.1 (b) above, no patent license is
    granted by a Contributor:
        for any code that a Contributor has removed from Covered Software; or
        for infringements caused by: (i) Your and any other third party's
        modifications of Covered Software, or (ii) the combination of its
        Contributions with other software (except as part of its
        Contributor Version); or
        under Patent Claims infringed by Covered Software in the absence
        of its Contributions.
    This License does not grant any rights in the trademarks, service
    marks, or logos of any Contributor (except as may be necessary to
    comply with the notice requirements in Section 3.4). 2.4. Subsequent
    Licenses
    No Contributor makes additional grants as a result of Your choice to
    distribute the Covered Software under a subsequent version of this
    License (see Section 10.2) or under the terms of a Secondary License
    (if permitted under the terms of Section 3.3). 2.5. Representativeation
    Each Contributor represents that the Contributor believes its
    Contributions are its original creation (s) or it has sufficient rights
    to grant the rights to its Contributions conveyed by this License.
    2.6. Fair use
    This License is not intended to limit any rights you have under
    applicable copyright doctrines of fair use, fair dealing, or other
    equivalents. 2.7. Conditions
    Sections 3.1, 3.2, 3.3, and 3.4 are conditions of the licenses granted
    in Section 2.1. 3. Responsibilities 3.1. Distribution of source form
    All distribution of Covered Software in Source Code Form, including
    any Modifications that You create or to which You contribute, must be
    under the terms of this License. You must inform recipients that the
    Source Code Form of the Covered Software is governed by the terms of
    this License, and how they can obtain a copy of this License. You may
    not attempt to alter or restrict the recipients' rights in the Source
    Code Form. 3.2. Distribution of Executable Form
    If You distribute Covered Software in Executable Form then:
        such Covered Software must also be made available in Source Code
        Form, as described in Section 3.1, and You must inform recipients
        of the Executable Form how they can obtain a copy of such Source
        Code Form by reasonable means in a timely manner, at a charge no
        more than the cost of distribution to the recipient; and
        You may distribute such Executable Form under the terms of this
        License, or sublicense it under different terms, provided that the
        license for the Executable Form does not attempt to limit or alter
        the recipients' rights in the Source Code Form under this License.
    3.3. Distribution of a larger work
    You may create and distribute a Larger Work under terms of Your
    choice, provided that you also comply with the requirements of this
    License for the Covered Software. If the Larger Work is a combination
    of Covered Software with a work governed by one or more Secondary
    Licenses, and the Covered Software is not Incompatible With Secondary
    Licenses, this License permits You to additionally distribute such
    Covered Software under the terms of such Secondary License (s), so that
    the recipient of the Larger Work may, at their option, further
    distribute the Covered Software under the terms of either this License
    or such Secondary License (s). 3.4. Notices
    You may not remove or alter the substance of any license notices
    (including copyright notices, patent notices, disclaimers of warranty,
    or limitations of liability) contained within the Source Code Form of
    the Covered Software, except that You may alter any license notices to
    the extent required to remedy known factual inaccuracies.
    3.5. Application of Additional Terms
    You may choose to offer, and to charge a fee for, warranty, support,
    indemnity or liability obligations to one or more recipients of
    Covered Software. However, You may do so only on Your own behalf, and
    not on behalf of any Contributor. You must make it absolutely clear
    that any such warranty, support, indemnity, or liability obligation is
    offered by You alone, and You hereby agree to indemnify every
    Contributor for any liability incurred by such Contributor as a result
    of warranty, support, indemnity or liability terms You offer. You may
    include additional disclaimers of warranty and limitations of
    liability specific to any jurisdiction. 4. Inability to Comply Due to
    Statute or regulation
    If it is impossible for you to comply with any of the terms of this
    License with respect to some or all of the Covered Software due to
    statute, judicial order, or regulation then You must: (a) comply with
    the terms of this License to the maximum extent possible; and (b)
    describe the limitations and the code they affect. Such description
    must be placed in a text file included with all distributions of the
    Covered Software under this License. Except to the extent prohibited
    by statute or regulation, such description must be sufficient
    detailed for a recipient of ordinary skill to be able to understand
    it. 5. Termination
    5.1. The rights granted under this License will terminate
    automatically if You fail to comply with any of its terms. However, if
    You become compliant, then the rights granted under this License from
    a particular Contributor are reinstated (a) provisionally, unless and
    until such Contributor explicitly and finally terminates Your grants,
    and (b) on an ongoing basis, if such Contributor fails to notify You
    of the non-compliance by some reasonable means prior to 60 days after
    You have come back into compliance. Moreover, Your grants from a
    particular Contributor are reinstated on an ongoing basis if such
    Contributor notifies You of the non-compliance by some reasonable
    means, this is the first time You have received notice of
    non-compliance with this License from such Contributor, and You become
    compliant prior to 30 days after Your receipt of the notice.
    5.2. If You initiate litigation against any entity by asserting a
    patent infringement claim (excluding declaratory judgment actions,
    counter-claims, and cross-claims) alleging that a Contributor Version
    directly or indirectly infringes any patent, then the rights granted
    to you by any and all Contributors for the Covered Software under
    Section 2.1 of this License shall terminate.
    5.3. In the event of termination under Sections 5.1 or 5.2 above, all
    end user license agreements (excluding distributors and resellers)
    which have been validly granted by You or Your distributors under this
    License prior to termination shall survive termination. 6. Disclaimer
    of warranty
    Covered Software is provided under this License on an “as is” basis,
    without warranty of any kind, either expressed, implied, or statutory,
    including, without limitation, warranties that the Covered Software is
    free of defects, merchantable, fit for a particular purpose or
    non-infringing. The entire risk as to the quality and performance of
    the Covered Software is with You. Should any Covered Software prove
    defective in any respect, You (not any Contributor) assume the cost of
    any necessary servicing, repair, or correction. This disclaimer of
    warranty constitutes an essential part of this License. No use of any
    Covered Software is authorized under this License except under this
    disclaimer. 7. Limitation of Liability
    Under no circumstances and under no legal theory, whether tort
    (including negligence), contract, or otherwise, shall any Contributor,
    or anyone who distributes covered software as permitted above, be
    liable to You for any direct, indirect, special, incidental, or
    consequential damages of any character including, without limitation,
    damages for lost profits, loss of goodwill, work stoppage, computer
    failure or malfunction, or any and all other commercial damages or
    losses, even if such party shall have had informed of the possibility
    of such damages. This limitation of liability shall not apply to
    liability for death or personal injury resulting from such party's
    negligence to the extent applicable law prohibits such
    limitation. Some jurisdictions do not allow the exclusion or
    limitation of incidental or consequential damages, so this exclusion
    and limitation may not apply to you. 8. Litigation
    Any litigation relating to this License may be brought only in the
    courts of a jurisdiction where the defendant maintains its principal
    place of business and such litigation shall be governed by laws of
    that jurisdiction, without reference to its conflict-of-law
    provisions. Nothing in this Section shall prevent a party's ability to
    bring cross-claims or counter-claims. 9. Miscellaneous
    This License represents the complete agreement regarding the subject
    matter hereof. If any provision of this License is held to be
    unenforceable, such provision shall be reformed only to the extent
    necessary to make it enforceable. Any law or regulation which provides
    that the language of a contract shall be construed against the drafter
    shall not be used to construe this License against a Contributor.
    10. Versions of the License 10.1. New versions
    Mozilla Foundation is the license steward. Except as provided in
    Section 10.3, no one other than the license steward has the right to
    modify or publish new versions of this License. Each version will be
    given a distinguishing version number. 10.2. Effect of new versions
    You may distribute the Covered Software under the terms of the version
    of the License under which You originally received the Covered
    Software, or under the terms of any subsequent version published by
    the license steward. 10.3. Modified Versions
    If you create software not governed by this License, and you want to
    create a new license for such software, you may create and use a
    modified version of this License if you rename the license and remove
    any references to the name of the license steward (except to note that
    such modified license differs from this License). 10.4. Distributing
    Source Code Form that is Incompatible With Secondary Licenses
    If You choose to distribute Source Code Form that is Incompatible With
    Secondary Licenses under the terms of this version of the License, the
    notice described in Exhibit B of this License must be attached.
    Exhibit A - Source Code Form License Notice
        This Source Code Form is subject to the terms of the Mozilla
        Public License, v. 2.0. If a copy of the MPL was not distributed
        with this file, You can obtain one at http://mozilla.org/MPL/2.0/.
    If it is not possible or desirable to put the notice in a particular
    file, then You may include the notice in a location (such as a LICENSE
    file in a relevant directory) where a recipient would be likely to
    look for such a notice.
    You may add additional accurate notices of copyright ownership.
    Exhibit B - “Incompatible With Secondary Licenses” Notice
        This Source Code Form is “Incompatible With Secondary Licenses”,
        as defined by the Mozilla Public License, v. 2.0.
    Comment by lorus
    For an open source project, it's worth considering MPL 2.0. A kind of license, something between LGPL and BSD. It differs from LGPL in the absence of static binding problems. This may be important for programs in the PL, in which dynamic linking is not provided.
    In the case of using an unchanged library under MPL 2.0, as part of a larger project, you just need to specify where you can get the source code for this library. But if you still change the code, then you must provide access to the code you modified under the same MPL 2.0. That is, the copyleft license. Here's a little clarification from Athari :
    The MPL license infects files, not projects, unlike the (L) GPL. If you modify the file, it should remain under the MPL. If you add - there are no restrictions.
    If the project is under the GNU GPL, then you must make the code used in it under MPL 2.0 available immediately under both licenses.

    To use this license in your project you need to add text from the Exhibit A license
    This Source Code Form is subject to the terms of the Mozilla
    Public License, v. 2.0. If a copy of the MPL was not distributed
    with this file, You can obtain one at http://mozilla.org/MPL/2.0/.
    as a header in each source code file. The license does not require copyright to be indicated in each file, but it does not prohibit this either. Also do not forget to add the LICENSE file with the license text to the project.

    EPL-1.0 (Eclipse Public License Version 1.0)
    License Text
    Eclipse Public License - v 1.0
    THE ACCOMPANYING PROGRAM IS PROVIDED UNDER THE TERMS OF THIS ECLIPSE
    PUBLIC LICENSE ("AGREEMENT"). ANY USE, REPRODUCTION OR DISTRIBUTION OF
    THE PROGRAM CONSTITUTES RECIPIENT'S ACCEPTANCE OF THIS AGREEMENT.
    1. DEFINITIONS
    "Contribution" means:
      a) in the case of the initial Contributor, the initial code and
         documentation distributed under this Agreement, and
      b) in the case of each subsequent Contributor:
        i) changes to the Program, and
        ii) additions to the Program;
    where such changes and / or additions to the Program originate from and
    are distributed by that particular Contributor. A contributing
    'originates' from a Contributor if it was added to the Program by such
    Contributor itself or anyone acting on such Contributor's
    behalf. Contributions do not include additions to the Program which:
    (i) are separate modules of software distributed in conjunction with
    the Program under their own license agreement, and (ii) are not
    derivative works of the Program.
    "Contributor" means any person or entity that distributes the Program.
    "Licensed Patents" mean patent claims licensable by a Contributor
    which are necessarily infringed by the use or sale of its Contribution
    alone or when combined with the Program.
    "Program" means the Contributions distributed in accordance with this
    Agreement.
    "Recipient" means anyone who receives the Program under this
    Agreement, including all Contributors.
    2. GRANT OF RIGHTS
      a) Subject to the terms of this Agreement, each Contributor hereby
         grants Recipient a non-exclusive, worldwide, royalty-free
         copyright license to reproduce, prepare derivative works of,
         publicly display, publicly perform, distribute and sublicense the
         Contribution of such Contributor, if any, and such derivative
         works, in source code and object code form.
      b) Subject to the terms of this Agreement, each Contributor hereby
         grants Recipient a non-exclusive, worldwide, royalty-free patent
         license under Licensed Patents to make, use, sell, offer to sell,
         import and otherwise transfer the Contribution of such
         Contributor, if any, in source code and object code form. This
         patent license shall apply to the combination of the Contribution
         and the Program if, at the time the Contribution is added by the
         Contributor, such addition of the Contribution causes such
         combination to be covered by the Licensed Patents. The patent
         license shall not apply to any other combinations which include
         the Contribution. No hardware per se is licensed hereunder.
      c) Recipient understands that although each Contributor grants the
         licenses to its Contributions set forth forth, no assurances are
         provided by any Contributor that the Program does not infringe
         the patent or other intellectual property rights of any other
         entity. Each Contributor disclaims any liability to Recipient for
         claims brought by any other entity based on infringement of
         intellectual property rights or otherwise. As a condition to
         exercising the rights and licenses granted hereunder, each
         Recipient hereby assumes sole responsibility to secure any other
         intellectual property rights needed, if any. For example, if a
         third party patent license is required to allow Recipient to
         distribute the Program, it is Recipient's responsibility to
         acquire that license before distributing the Program.
      d) Each Contributor represents that to its knowledge it has
         sufficient copyright rights in its Contribution, if any, to grant
         the copyright license set forth in this Agreement.
    3. REQUIREMENTS
    A Contributor may choose to distribute the Program in object code form
    under its own license agreement, provided that:
      a) it complies with the terms and conditions of this Agreement; and
      b) its license agreement:
        i) effectively disclaims on behalf of all Contributors all
           warranties and conditions, express and implied, including
           warranties or conditions of title and non-infringement, and
           implied warranties or conditions of merchantability and fitness
           for a particular purpose;
        ii) effectively excludes on behalf of all Contributors all
            liability for damages, including direct, indirect, special,
            incidental and consequential damages, such as lost profits;
        iii) states that any provisions which differ from this Agreement
             are offered by that Contributor alone and not by any other
             party; and
        iv) states that source code for the Program is available from such
            Contributor, and informs licensees how to obtain it in a
            reasonable manner on or through a medium customarily used for
            software exchange.
    When the Program is made available in source code form:
      a) it must be made available under this Agreement; and
      b) a copy of this Agreement must be included with each copy of the Program.
    Contributors may not remove or alter any copyright notices contained
    within the Program.
    Each Contributor must identify itself as the originator of its
    Contribution, if any, in a manner that reasonably allows subsequent
    Recipients to identify the originator of the Contribution.
    4. COMMERCIAL DISTRIBUTION
    Commercial distributors of software may accept certain
    responsibilities with respect to end users, business partners and the
    like. While this license is intended to facilitate the commercial use
    of the Program, the Contributor who includes the Program in a
    commercial product offering should do so in a manner which does not
    create potential liability for other Contributors. Therefore, if a
    Contributor includes the Program in a commercial product offering,
    such Contributor ("Commercial Contributor") hereby agrees to defend
    and indemnify every other Contributor ("Indemnified Contributor")
    against any losses, damages and costs (collectively "Losses") arising
    from claims, lawsuits and other legal actions brought by a third party
    against the Indemnified Contributor to the extent caused by the acts
    or omissions of such Commercial Contributor in connection with its
    distribution of the Program in a commercial product offering. The
    obligations in this section do not apply to any claims or Losses
    relating to any actual or alleged intellectual property
    infringement. In order to qualify, an Indemnified Contributor must: a)
    promptly notify the Commercial Contributor in writing of such claim,
    and b) allow the Commercial Contributor to control, and cooperate with
    the Commercial Contributor in, the defense and any related settlement
    negotiations. The Indemnified Contributor may participate in any such
    claim at its own expense.
    For example, a Contributor might include the Program in a commercial
    product offering, Product X. That Contributor is then a Commercial
    Contributor If that Commercial Contributor then makes performance
    claims, or offers warranties related to Product X, those performance
    claims and warranties are such Commercial Contributor's responsibility
    alone. Under this section, the Commercial Contributor would have to
    defend claims against the other Contributors related to those
    performance claims and warranties, and if a court requires any other
    Contributor to pay any damages as a result, the Commercial Contributor
    must pay those damages.
    5. NO WARRANTY
    EXCEPT AS EXPRESSLY SET FORTH IN THIS AGREEMENT, THE PROGRAM IS
    PROVIDED ON AN "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
    KIND, EITHER EXPRESS OR IMPLIED INCLUDING, WITHOUT LIMITATION, ANY
    WARRANTIES OR CONDITIONS OF TITLE, NON-INFRINGEMENT, MERCHANTABILITY
    OR FITNESS FOR A PARTICULAR PURPOSE. Each recipient is solely
    responsible for determining the appropriateness of using and
    distributing the Program and assumes all risks associated with its
    exercise of rights under this agreement, including but not limited to
    the risks and costs of program errors, compliance with applicable
    laws, damage to or loss of data, programs or equipment, and
    unavailability or interruption of operations.
    6. DISCLAIMER OF LIABILITY
    EXCEPT AS EXPRESSLY SET FORTH IN THIS AGREEMENT, NEITHER RECIPIENT NOR
    ANY CONTRIBUTORS SHALL HAVE ANY LIABILITY FOR ANY DIRECT, INDIRECT,
    INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING
    WITHOUT LIMITATION LOST PROFITS), HOWEVER CAUSED AND ON ANY THEORY OF
    LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
    NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OR
    DISTRIBUTION OF THE PROGRAM OR THE EXERCISE OF ANY RIGHTS GRANTED
    HEREUNDER, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGES.
    7. GENERAL
    If any provision of this Agreement is invalid or unenforceable under
    applicable law, it shall not affect the validity or enforceability of
    the remainder of the terms of this Agreement, and without further
    action by the parties hereto, such provision shall be reformed to the
    minimum extent necessary to make such provision valid and enforceable.
    If Recipient institutes patent litigation against any entity
    (including a cross-claim or counterclaim in a lawsuit) alleging that
    the Program itself (excluding combinations of the Program with other
    software or hardware) infringes such Recipient's patent (s), then such
    Recipient's rights granted under Section 2 (b) shall terminate as of
    the date such litigation is filed.
    All Recipient's rights under this Agreement shall terminate if it
    fails to comply with any of the material terms or conditions of this
    Agreement and does not cure such failure in a reasonable period of
    time after becoming aware of such noncompliance. If all Recipient's
    rights under this Agreement terminate, Recipient agrees to cease use
    and distribution of the Program as soon as reasonably
    practicable. However, Recipient's obligations under this Agreement and
    any licenses granted by Recipient relating to the Program shall
    continue and survive.
    Everyone is permitted to copy and distribute copies of this Agreement,
    but in order to avoid inconsistency the Agreement is copyrighted and
    may only be modified in the following manner. The Agreement Steward
    reserves the right to publish new versions (including revisions) of
    this Agreement from time to time. No one other than the Agreement
    Steward has the right to modify this Agreement. The eclipse foundation
    is the initial Agreement Steward. The Eclipse Foundation may assign
    the responsibility to serve as the Agreement Steward to a suitable
    separate entity. Each new version of the Agreement will be given a
    distinguishing version number. The Program (including Contributions)
    may always be distributed subject to the version of the Agreement
    under which it was received. In addition, after a new version of the
    Agreement is published, Contributor may elect to distribute the
    Program (including its Contributions) under the new version. Except as
    expressly stated in Sections 2 (a) and 2 (b) above, Recipient receives
    no rights or licenses to the intellectual property of any Contributor
    under this Agreement, whether expressly, by implication, estoppel or
    otherwise. All rights in the Program not expressly granted under this
    Agreement are reserved.
    This Agreement is governed by the laws of the State of New York and
    the intellectual property laws of the United States of America. No
    party to this Agreement will bring a legal action under this Agreement
    more than one year after the cause of action arose. Each party waives
    its rights to a jury trial in any resulting litigation.
    At the request of kidar2 , I add an EPL license. This is a copyleft license, but it is not compatible with the GNU GPL.

    When distributed in source code form, the program must be available under the EPL license.

    The author is allowed to distribute the program in the form of object code under his own license, provided that: this license complies with the EPL conditions, expressly disclaims any warranties and liability on behalf of all authors, indicates that the source codes of the program are available from this author and explains how they receive.

    Application to your project: a copy of the license must be included in all copies of the program

    Ms-PL (Microsoft Public License)
    License Text
    Microsoft Public License (Ms-PL)
    This license governs use of the accompanying software. If you use the
    software, you accept this license. If you do not accept the license,
    do not use the software.
     1. Definitions
        The terms "reproduce," "reproduction," "derivative works," and
        "distribution" have the same meaning here as under US copyright
        law.
        A "contribution" is the original software, or any additions or
        changes to the software.
        A "contributor" is any person that distributes its contribution
        under this license.
        "Licensed patents" are a contributor's patent claims that read
        directly on its contribution.
     2. Grant of Rights
        (A) Copyright Grant- Subject to the terms of this license,
        including the license conditions and limitations in section 3,
        each contributor grants you a non-exclusive, worldwide,
        royalty-free copyright license to reproduce its contribution,
        prepare derivative works of its contribution, and distribute its
        contribution or any derivative works that you create.
        (B) Patent Grant- Subject to the terms of this license, including
        the license conditions and limitations in section 3, each
        contributor grants you a non-exclusive, worldwide, royalty-free
        license under its licensed patents to make, have made, use, sell,
        offer for sale, import, and / or otherwise dispose of its
        contribution in the software or derivative works of the
        contribution in the software.
     3. Conditions and Limitations
        (A) No Trademark License- This license does not grant you rights
        to use any contributors' name, logo, or trademarks.
        (B) If you bring a patent claim against any contributor over
        patents that you claim are infringed by the software, your patent
        license from such contributor to the software ends automatically.
        (C) If you distribute any portion of the software, you must retain
        all copyright, patent, trademark, and attribution notices that are
        present in the software.
        (D) If you distribute any portion of the software in source code
        form, you may do so only under this license by including a
        complete copy of this license with your distribution. If you
        distribute any portion of the software in compiled or object code
        form, you may only do so under a license that complies with this
        license.  
        (E) The software is licensed "as-is." You bear the risk of using
        it. The contributors give no express warranties, guarantees, or
        conditions. You may have additional consumer rights under your
        local laws which this license cannot change. To the extent
        permitted under your local laws, the contributors exclude the
        implied warranties of merchantability, fitness for a particular
        purpose and non-infringement.
    About the license reminded sensboston . Copyleft license incompatible with the GPL. The meaning is similar to the EPL, but written in a much, much more human language. The shortest copyleft license in this article.

    It has an even weaker copyleft than the EPL: if you distribute project source codes containing code under Ms-PL, then all project source codes must be distributed under Ms-PL. At the same time, distribution in the form of object code or binary form is allowed under any license that does not violate Ms-PL. In addition, you must retain all copyrights, patents, trademarks and authorship of the original code. Yes, the license governs patent relations.

    To apply to your project: copy the license text into your project (for example, in the LICENSE file) and distribute it with it.

    MIT
    License Text
     Copyright (c) 1998, 1999, 2000 Thai Open Source Software Center Ltd
     Permission is hereby granted, free of charge, to any person obtaining
     a copy of this software and associated documentation files (the
     "Software"), to deal in the Software without restriction, including
     without limitation the rights to use, copy, modify, merge, publish,
     distribute, sublicense, and / or sell copies of the Software, and to
     permit persons to whom the Software is furnished to do so, subject to
     the following conditions:
     The above copyright notice and this permission notice shall be included
     in all copies or substantial portions of the Software.
     THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
     EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
     MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
     IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
     CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
     TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
     SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
    There is a myth that a MIT license exists. The fact is that MIT (Massachusetts Institute of Technology) used many different licenses. That text, which is now called the MIT license, the original was licensed Expat , and before that was used for most of the license X11. This license is permissive, without copyleft. It allows the use and modification of the code in almost any way, provided that the text of the license itself and the attribution do not disappear, even if you break the original project into pieces. Also, the indisputable advantage of this license is its small size. The lack of regulation of patent relations is noted as a drawback. Because of this, GNU recommends using a different licensing license instead - Apache 2.0, and MIT is offered to be used only for small projects. Nevertheless, this is probably the most famous of the licensing licenses.

    To apply it to your project, create a LICENSE text file and place the license text there, and do not forget to replace the data in the copyright line with the correct one. Many additionally indicate the full text of the license in the header of each source code file.

    Apache 2.0
    License Text
                                     Apache license
                               Version 2.0, January 2004
                            http://www.apache.org/licenses/
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    Наиболее современная и сбалансированная из разрешительных лицензий. Написана человеческим языком, но с оглядкой на современное правоприменение, в частности, упомянутые выше патентные отношения (пункт 3 лицензии). GNU советуют применять именно эту лицензию, когда вам необходима разрешительная лицензия.

    Для применения лицензии Apache 2.0 к вашему проекту, нужно добавить в него файл LICENSE, содержащий текст лицензии. Кроме того, в APPENDIX лицензии нам предлагают добавлять в качестве шапки в каждый файл исходного кода следующий текст:

    Copyright [yyyy] [name of copyright owner]
    Licensed under the Apache License, Version 2.0 (the "License");
    you may not use this file except in compliance with the License.
    You may obtain a copy of the License at
        http://www.apache.org/licenses/LICENSE-2.0
    Unless required by applicable law or agreed to in writing, software
    distributed under the License is distributed on an "AS IS" BASIS,
    WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    See the License for the specific language governing permissions and
    limitations under the License.

    Но при этом сама лицензия выдвигает следующие требования:
    made available under the License, as indicated by a copyright notice that is included in or attached to the work (an example is provided in the Appendix below)
    copyright notice — это как раз строка, указывающая правообладателя. А «made available under the License, as indicated» означает, что еще должна быть явно указана лицензия. То есть, допустимо что-то вида:

    Copyright [yyyy] [name of copyright owner]
    Licensed under the Apache License, Version 2.0

    Причем, совсем необязательно в исходном коде — Apache 2.0 позволяет для этого использовать файл NOTICE («or attached to the work»).

    И еще о файле NOTICE: если в вашей работе вы используете чужой проект под лицензией Apache 2.0, содержащий свой файл NOTICE, то в этом случае вы обязаны копировать в производную работу содержимое файла NOTICE, в одно из трех мест: либо в аналогичный файл NOTICE, либо в исходные коды или документацию, распространяемую вместе с производной работой, либо в вывод производной работы (например в about-диалог); все согласно пункту 4 (d) лицензии. Заметьте, что, вопреки расхожему мнению, обязательного наличия файла NOTICE лицензия не требует.

    При распространении в бинарной форме, вы, кроме того, должны предоставлять копию лицензии вместе с программой.

    BSD
    Текст лицензии
    Redistribution and use in source and binary forms, with or without
    modification, are permitted provided that the following conditions are
    met:
        (1) Redistributions of source code must retain the above copyright
        notice, this list of conditions and the following disclaimer. 
        (2) Redistributions in binary form must reproduce the above copyright
        notice, this list of conditions and the following disclaimer in
        the documentation and/or other materials provided with the
        distribution.  
        (3)The name of the author may not be used to
        endorse or promote products derived from this software without
        specific prior written permission.
    THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
    IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
    WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
    DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT,
    INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
    (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
    SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
    HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
    STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
    IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
    POSSIBILITY OF SUCH DAMAGE.
    Это разрешительная лицензия, схожая по смыслу с лицензией MIT. Оригинальная лицензия BSD состояла из 4-х пунктов, но, впоследствии, 3-й пункт, требовавший включать уведомление об авторстве во все рекламные материалы, был исключен. Кроме того, существует и двухпунктовая лицензия BSD, о которой напомнил Athari, в ней удален третий пункт, и эта версия практически совпадает по функциональности с лицензией MIT. GNU советуют вместо лицензии BSD использовать MIT, чтобы исключить путаницу с тем, какая именно версия лицензии BSD используется.

    Для ее применения к своему проекту создайте текстовый файл LICENSE и поместите текст лицензии туда. Не забудьте добавить строку с копирайтом. Также, дополнительно можно указать полный текст лицензии в шапке каждого файла исходного кода.

    При распространении в бинарной форме лицензия и копирайт должны быть представлены в документации и/или других материалах, распространяемых вместе с бинарником.

    WTFPL Version 2
    Текст лицензии
                DO WHAT THE FUCK YOU WANT TO PUBLIC LICENSE
                        Version 2, December 2004
     Copyright (C) 2004 Sam Hocevar 
     Everyone is permitted to copy and distribute verbatim or modified
     copies of this license document, and changing it is allowed as long
     as the name is changed.
                DO WHAT THE FUCK YOU WANT TO PUBLIC LICENSE
       TERMS AND CONDITIONS FOR COPYING, DISTRIBUTION AND MODIFICATION
      0. You just DO WHAT THE FUCK YOU WANT TO.
    Как оказалось, весьма популярная на Хабре лицензия (спасибо Komzpa, Stasik0 и плюсовавшим). Кроме того, она присутствует в списке лицензий GNU, хотя они и постеснялись разместить ее текст на своем сайте.

    GNU классифицируют ее как разрешительную некопилефтную лицензию и не рекомендуют ее использовать без каких-либо объяснений. Вместо нее предлагаются MIT или Apache 2.0.

    Могу предположить причины:
    • во-первых, лицензия содержит лексику, которая может считаться ненормативной (и я не уверен, что в таком случае лицензию будут принимать в расчет, скажем, в суде),
    • во-вторых, в лицензии никак не прописан отказ от ответственности,
    • в-третьих, у меня есть подозрение, что разрешение пользователю делать с кодом все что угодно тоже может быть оспорено юристами.

    Чтобы применить ее к своему проекту — просто добавьте файл с лицензией в проект и не забудьте поменять в лицензии строку с копирайтом. Можно также добавить лицензию в шапку ко всем исходникам проекта.

    Beerware
    Текст лицензии
    /*
    * — * «THE BEER-WARE LICENSE» (Revision 42):
    * wrote this file. As long as you retain this notice you
    * can do whatever you want with this stuff. If we meet some day, and you think
    * this stuff is worth it, you can buy me a beer in return. Poul-Henning Kamp
    * — */
    Еще одна лицензия, набравшая плюсов в комменатриях (спасибо JDima и плюсовавшим). Это тоже разрешительная лицензия, которая пытается разрешить все (ключевое слово «пытается») и содержит необязательное условие поставить автору пива (в других версиях, выпить в честь автора) при встрече, если вам понравился его проект.

    Как известно, «чрезмерное употребление пива вредит вашему здоровью». Но беда этой лицензии не в пиве. Обратите внимание на фразу
    wrote this file. As long as you retain this notice...
    Теперь представьте, что вы изменили код этого файла. Или вы взяли код из этого файла, чтобы добавить в свой. Теперь фраза
    wrote this file.
    является неверной, но вы обязаны ее сохранить! То есть, лицензия пытается отобрать у вас право указывать авторство произведения. А, например, в России автор имеет неимущественные и неотчуждаемые право авторства и право автора на имя. Получается, что такая лицензия, разрешая изменения и использование кода и запрещая указывать новых авторов, является незаконной (по-хорошему, нужно уточнить у юриста).

    Общественное достояние (Public Domain)
    Это, конечно же, не лицензия. Но многие рассматривают перевод произведения в общественное достояние как способ сложить с себя имущественные права. Периодически люди пытаются сделать это и в отношении программ. Обычно просто пишут, что проект находится в Public Domain и радуются, что все смогут им пользоваться. Но на самом деле это не так! В разных странах общественное достояние разное. Причем, в большинстве из них закон явно не предусматривает механизмов для перевода произведения в общественное достояние по желанию автора! Например, в России переход в общественное достояние определен только по истечению срока действия защиты авторского права. В США, насколько мне известно, досрочной процедуры тоже не предусмотрено. Кроме того, могут быть сложности и с использованием произведений, находящихся в общественном достоянии. Скажем, в Уругвае, для того, чтобы использовать произведение из общественного достояния, вам понадобится уплатить пошлину государству и получить разрешение специальной комиссии, которая удостоверится, что вы не будете использовать данное произведение как-то непотребно (правда, я не знаю, работает ли все это в отношении программ). Вследствие подобных нюансов, появились лицензии подобные следующей.

    CC0 (Creative Commons CC0)
    Текст лицензии
         CREATIVE COMMONS CORPORATION IS NOT A LAW FIRM AND DOES NOT
         PROVIDE LEGAL SERVICES. DISTRIBUTION OF THIS DOCUMENT DOES NOT
         CREATE AN ATTORNEY-CLIENT RELATIONSHIP. CREATIVE COMMONS PROVIDES
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         WARRANTIES REGARDING THE USE OF THIS DOCUMENT OR THE INFORMATION
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         RESULTING FROM THE USE OF THIS DOCUMENT OR THE INFORMATION OR
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    Statement of Purpose
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    For these and/or other purposes and motivations, and without any
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    include, but are not limited to, the following:
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        a Work; database rights (such as those arising under Directive
        96/9/EC of the European Parliament and of the Council of 11 March
        1996 on the legal protection of databases, and under any national
        implementation thereof, including any amended or successor version
        of such directive); and other similar, equivalent or corresponding
        rights throughout the world based on applicable law or treaty, and
        any national implementations thereof.
    2. Waiver. To the greatest extent permitted by, but not in
    contravention of, applicable law, Affirmer hereby overtly, fully,
    permanently, irrevocably and unconditionally waives, abandons, and
    surrenders all of Affirmer's Copyright and Related Rights and
    associated claims and causes of action, whether now known or unknown
    (including existing as well as future claims and causes of action), in
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    limitation commercial, advertising or promotional purposes (the
    "Waiver"). Affirmer makes the Waiver for the benefit of each member of
    the public at large and to the detriment of Affirmer's heirs and
    successors, fully intending that such Waiver shall not be subject to
    revocation, rescission, cancellation, termination, or any other legal
    or equitable action to disrupt the quiet enjoyment of the Work by the
    public as contemplated by Affirmer's express Statement of Purpose.
    3. Public License Fallback. Should any part of the Waiver for any
    reason be judged legally invalid or ineffective under applicable law,
    then the Waiver shall be preserved to the maximum extent permitted
    taking into account Affirmer's express Statement of Purpose. In
    addition, to the extent the Waiver is so judged Affirmer hereby grants
    to each affected person a royalty-free, non transferable, non
    sublicensable, non exclusive, irrevocable and unconditional license to
    exercise Affirmer's Copyright and Related Rights in the Work (i) in
    all territories worldwide, (ii) for the maximum duration provided by
    applicable law or treaty (including future time extensions), (iii) in
    any current or future medium and for any number of copies, and (iv)
    for any purpose whatsoever, including without limitation commercial,
    advertising or promotional purposes (the "License"). The License shall
    be deemed effective as of the date CC0 was applied by Affirmer to the
    Work. Should any part of the License for any reason be judged legally
    invalid or ineffective under applicable law, such partial invalidity
    or ineffectiveness shall not invalidate the remainder of the License,
    and in such case Affirmer hereby affirms that he or she will not (i)
    exercise any of his or her remaining Copyright and Related Rights in
    the Work or (ii) assert any associated claims and causes of action
    with respect to the Work, in either case contrary to Affirmer's
    express Statement of Purpose.
    4. Limitations and Disclaimers.
        No trademark or patent rights held by Affirmer are waived,
        abandoned, surrendered, licensed or otherwise affected by this
        document.  Affirmer offers the Work as-is and makes no
        representations or warranties of any kind concerning the Work,
        express, implied, statutory or otherwise, including without
        limitation warranties of title, merchantability, fitness for a
        particular purpose, non infringement, or the absence of latent or
        other defects, accuracy, or the present or absence of errors,
        whether or not discoverable, all to the greatest extent
        permissible under applicable law.  Affirmer disclaims
        responsibility for clearing rights of other persons that may apply
        to the Work or any use thereof, including without limitation any
        person's Copyright and Related Rights in the Work. Further,
        Affirmer disclaims responsibility for obtaining any necessary
        consents, permissions or other rights required for any use of the
        Work.  Affirmer understands and acknowledges that Creative Commons
        is not a party to this document and has no duty or obligation with
        respect to this CC0 or use of the Work.
    Creative Commons CC0 — лицензия, которая пытается перевести проект в общественное достояние в максимальной форме, разрешенной законом. А если закон не позволяет это совершить, автоматически применяет положения разрешительной лицензии. GNU рекомендует применять CC0 в том случае, если вы хотите перевести вашу работу в общественное достояние.

    Про применение CC0 к проекту можно прочитать в этой статье.

    Unlicense
    Текст лицензии
    This is free and unencumbered software released into the public domain.
    Anyone is free to copy, modify, publish, use, compile, sell, or
    distribute this software, either in source code form or as a compiled
    binary, for any purpose, commercial or non-commercial, and by any
    means.
    In jurisdictions that recognize copyright laws, the author or authors
    of this software dedicate any and all copyright interest in the
    software to the public domain. We make this dedication for the benefit
    of the public at large and to the detriment of our heirs and
    successors. We intend this dedication to be an overt act of
    relinquishment in perpetuity of all present and future rights to this
    software under copyright law.
    THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
    EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
    MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
    IN NO EVENT SHALL THE AUTHORS BE LIABLE FOR ANY CLAIM, DAMAGES OR
    OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
    ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
    OTHER DEALINGS IN THE SOFTWARE.
    For more information, please refer to 
    Про лицензию напомнил Athari. Эта лицензия появилась путем копипасты текста о передаче в общественное достояние и отказа от прав (waiver) проекта SQLite и отказа от гарантий из лицензии MIT. Аналогично лицензии CC0, Unlicense пытается перевести работу в общественное достояние и послужить в виде лицензионного договора на случай, если этого не произошло. Однако, эта лицензия менее проработана, чем CC0, из-за чего может являться нелегальной. Вот в этом вопросе на stackexchange подробнее. Вкратце, там указано, что лицензия явно нелегальна, например, в Германии, так как там, похоже, нет понятия общественного достояния. А Unlicense, в отличие от CC0, не отказывается от перевода в общественное достояние для случая, когда это противоречит закону. Кроме того лицензия как минимум нелогична (или даже противоречива), так как передача в общественное достояние, заявленная в первой строке, в случае успеха делает невалидными параграфы, следующие за ней.

    Для применения Unlicense нужно добавить файл с текстом лицензии к вашему проекту. Авторы лицензии рекомендуют назвать файл UNLICENSE.

    Copyright в исходниках


    Наверное, вы заметили, что многие лицензии предлагают размещать определенный текст в виде комментария в шапке файла? Если это является обязательным требованием, то тогда ему нужно следовать. Но насколько необходим подобный текст, если явного требования лицензия не предъявляет?

    Хорошие новости: в таком случае лицензию и даже копирайт совершенно не обязательно указывать в шапке файла. Ваша работа и так ваша, для подтверждения этого указывать копирайт нет необходимости. Подтверждать авторство или обладание правами вам все равно придется другими способами, а текст лицензии может находиться в отдельном файле.

    Но все же такой заголовок лучше иметь. Основные причины следующие:
    • Он четко показывает, что права на код кому-то принадлежат. Отмазки вида «я не знал, там не написано, не смог найти, не заметил» уже не прокатят. Иначе говоря, наличие такого заголовка предотвращает случайное неправомерное использование кода, а также может увеличить ответственность за намеренное.
    • Дает возможность идентифицировать владельца прав на код, чтобы связаться с ним в том числе и по вопросам правомерности использования этого кода.

    Между прочим, это имеет смысл не только для open-source проекта. Указание владельца прав и авторства может помочь и проприетарному коду в том случае, если он каким-либо образом утечет в сеть.

    Если вы решили, что уведомление о правах на файл исходного кода вам необходимо, то вот что оно должно содержать в идеале:
    • Copyright — так как в некоторых странах одного символа копирайта недостаточно для юридической значимости уведомления.
    • © — символ копирайта, в большинстве стран он необходим и достаточен для придания юридической значимости уведомлению. Простой буквы c в скобках ( c ) для этого может быть недостаточно. Используйте уже Unicode!
    • 2007, 2009, 2010 – 2012 — «годы жизни» кода, первое число — год, когда продукт был впервые опубликован, далее — годы, когда код обновлялся. Если годы, когда код в файле правился, идут не подряд, то их нужно указывать через запятую.
    • John Doe — имя владельца авторских прав. Не автора, это могут быть разные лица! Может быть именем человека, названием компании, или именами нескольких человек. Правда, в последнем случае лучше сделать отдельную строчку на каждого человека.
    • All rights reserved — «все права защищены», означает, что указанные лица обладают всеми правами на код. Дополнительное усиление уведомления копирайта, в случае обладания исключительными правами.
    • Если возможно, то дать ссылку на лицензионный договор или указание, где его искать.
    • Указать контактные данные.

    Обратите внимание, что имя автора в уведомление не входит. Автора/авторов можно указать отдельно, например, на следующей строке, в свободной форме (например Author: Jane Doe).

    Ну и, на всякий случай, примеры
    // Copyright © 2022 John Doe. All rights reserved.
    

    // Copyright © 2022-2096 Acme Corporation. All rights reserved.
    // Author: John Doe
    

    // Copyright © 2022 John Doe
    // Copyright © 2023-2028 Jane Doe
    // Copyright © 2028-2096 Acme Corporation. Contacts: 
    // License: http://opensource.org/licenses/MIT
    

    Заключение


    Разместить ваш проект в интернете и написать «пользуйтесь все!» еще недостаточно для того, чтобы им действительно начали пользоваться. И речь не о рекламе или полезности конкретного проекта. Часто необходимо четкое понимание, как можно и как нельзя использовать проект, особенно, если цели использования — коммерческие. В том числе, слова «пользуйтесь все» вряд ли удастся представить договором с правообладателем в случае каких-либо проблем.

    При выборе лицензии задумайтесь, в первую очередь, о том, что лицензию вы пишете в большей степени не для себя, а для тех, кто вашим кодом будет пользоваться. Она регулирует ваши отношения с ними. Кто будет использовать ваш код? Как они будут его использовать? Какая из лицензий будет им удобнее? Какие проблемы из-за лицензии могут возникнуть у них? А у вас? Ответив на подобные вопросы, можно подобрать наилучшую лицензию.

    В свою очередь, если вы используете чужой проект в своих целях, то нужно понять ограничения, накладываемые на вас его лицензией. Подходят ли они вам, сможете ли вы выполнить эти требования?

    Лицензия, даже свободная, является договором между правообладателем и пользователем. Старайтесь рассматривать это именно так.

    Материалы


    1. Право интеллектуальной собственности. Шпаргалка, Коллектив авторов
    2. Служебное произведение, Википедия
    3. Moral rights, Wikipedia
    4. Лицензия на программное обеспечение, Википедия
    5. Определение свободного программного обеспечения, Википедия
    6. Критерии Debian по определению свободного программного обеспечения, Википедия
    7. Свободная лицензия, Википедия
    8. Проприетарное программное обеспечение, Википедия
    9. Ричард Столлман, Википедия
    10. Брюс Перенс, Википедия
    11. Открытое программное обеспечение, Википедия
    12. Разрешительная лицензия свободного ПО, Википедия
    13. Various licenses and comments about them/Различные лицензии и комментарии к ним, GNU
    14. Копилефт, Википедия
    15. Understanding Open Source and Free Software Licensing, Andrew M. St. Laurent
    16. GNU Lesser General Public License, Википедия
    17. Почему вам не следует применять Меньшую GPL для своей следующей библиотеки, GNU
    18. Frequently Asked Questions about the GNU Licenses, GNU
    19. Как применять лицензии GNU со своими программами, GNU
    20. Лицензия BSD, Википедия
    21. Общественное достояние, Википедия
    22. Ley 9.739, Propiedad literaria y artistica, leyes de la República Oriental del Uruguay
    23. Uruguay: Dominio Público pero Pagante, Fundación Karisma con Open Business Latinamerica and the Caribbean
    24. Managing copyright information within a free software project, Software Freedom Law Center
    25. Using copyright notices, The UK Copyright Service
    26. Get rid of source code templates, Ville Laurikari
    27. MPL 2.0 FAQ, Mozilla Foundation
    28. «The Beerware License» Considered Harmful, RM
    29. How does MS-PL license work? Stackoverflow
    30. Unlicense Yourself: Set Your Code Free
    31. What is wrong with the Unlicense?

    Update
    Добавил GNU GPL Version 2, спасибо, wholeman
    Добавил MPL Version 2.0, спасибо, lorus
    Поправлено описание GNU GPL, спасибо, coh
    Поправлено описание Apache 2.0, благодаря eyeofhell
    Добавил WTFPL Version 2, спасибо Komzpa, Stasik0 и плюсовавшим
    Добавил Beerware license, спасибо JDima и плюсовавшим
    Добавил GNU AGPL, спасибо coh, lorus
    Добавил EPL Version 1.0, спасибо, kidar2
    Добавил Ms-PL и ссылку на еще один список лицензий, спасибо, sensboston
    Добавил в описание GPLv2 и GPLv3 ссылку на «Практическое руководство по соответствию GPL», спасибо, Indexator
    Добавил ссылку на сайт LicenseIT, спасибо, sensboston
    Добавил в описание GPLv3 еще одну ссылку, еше раз спасибо, Indexator
    Добавил описание Unlicense и внес правки в описания LGPL, MPL, MIT, BSD, спасибо, Athari

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