The GNU General Public License, Version 3, 29 June 2007 (GPLv3)
===============================================================
> Copyright © 2007
> Free Software Foundation, Inc.
> <<http://fsf.org/>>
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