Free software licenses in a spectrum. Software may be combined under a license that can be reached by tracking the arrows forward from the licenses of all its components. The result must then carry the license in the target box, possibly with additions from the source licenses. Permissive licenses allow the software to become non-free, protective (copyleft) licenses prevent the component from becoming non-free, weakly protective (weak copyleft) licenses additionally allow it (often a software library) to be part of a larger non-free work.
David A. Wheeler (initial), redrawn by <a href="//commons.wikimedia.org/w/index.php?title=User:Idrisz19&amp;action=edit&amp;redlink=1" class="new" title="User:Idrisz19 (page does not exist)">Idrisz19</a>
CC BY 3.0
<ul><li><a href="//commons.wikimedia.org/wiki/File:Software_licensing_spectrum.png" title="File:Software licensing spectrum.png">File:Software_licensing_spectrum.png</a></li>
<li><a rel="nofollow" class="external text" href="https://www.mozilla.org/en-US/MPL/2.0/Revision-FAQ/">About MPL 2.0: Revision Process and Changes FAQ — Mozilla</a></li></ul>