All tools used to develop the Osiris system are licensed as Free Software under terms of the GNU General Public License. The definition of free software can be found in [4]. What is the most important Free doesn't refer to price but to freedom. 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.
Home-page of Free Software Foundation may be found at www.fsf.org.