> Please note that GeoGebra as a complete software program would probably not be considered "free" software according to the definition of that term which is used by the Free Software Foundation. This is because the restrictions on commercial use that apply to the GeoGebra installers, web services and language files add-ons might be seen to be a restriction on the software as a whole (thus making it "non-free"), even though the GeoGebra source code is made available under the GNU General Public License without restriction. You can rest assured that our license terms fully respect all existing licenses from third parties (including the GNU General Public License and all Creative Commons variants) and have been checked by an experienced law firm.
Note that "the GeoGebra source code is made available under the GNU General Public License without restriction"
I don't see how this is a contradiction in itself. It is very similar to dual-licensing for commercial use.
> Please note that GeoGebra as a complete software program would probably not be considered "free" software according to the definition of that term which is used by the Free Software Foundation. This is because the restrictions on commercial use that apply to the GeoGebra installers, web services and language files add-ons might be seen to be a restriction on the software as a whole (thus making it "non-free"), even though the GeoGebra source code is made available under the GNU General Public License without restriction. You can rest assured that our license terms fully respect all existing licenses from third parties (including the GNU General Public License and all Creative Commons variants) and have been checked by an experienced law firm.
Note that "the GeoGebra source code is made available under the GNU General Public License without restriction"
I don't see how this is a contradiction in itself. It is very similar to dual-licensing for commercial use.