User's Manual

118
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 Foundationʼs software and to any other
program whose authors commit to using it. (Some other
Free Software Foundation software is covered by the
GNU Library 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.