User's Manual
58
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) oer 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 modied
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 reect 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 eect 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 modication follow.