Several of the software packages listed in these appendices and included on the companion DVD—like Audacity and Gimp—are distributed under the terms of the GNU General Public License (GPL).
The text of the GPL is as follows:
GNU GENERAL PUBLIC LICENSE
Version 3, 29 June 2007
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.
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 ...