CptnObvious999 wrote:I don't think they have to purchase a commercial liceanse if it isn't for profit.
Ye they do, let's look at the facts: The Windows and Mac versions of Qt is released under the GPL, not the LGPL like GTK is, and the GPL requires any program that links to it and or includes code from it to also be released under the GPL. The X11 version of Qt, which basicly runs on any major UNIX/UNIX-like system our there is released under the GPL AND the QPL, the GPL part of the deal here does basicly the same as with the Windows and Mac version, but the QPL allows for distribution under open source licenses such as the BSD license or the MIT license (Which is basicly the same thing). What these facts basicly mean is that if you want to write proprietary closed source software using Qt, you HAVE to have a commercial license from Trolltech, because that allows you to bypass the terms of the GPL, which Trolltech can do because they own the copyrights to Qt and the rights to publish it under another license. So what this means is that if you want to write cross platform closed source software, you can't use Qt free of charge, if you want to write cross platform free software (I consider the GPL a free software license and stuff like the BSD license an open source license) then you can freely (Both as in price and freedom) use Qt to do that under the terms of the GNU General Public License.
CptnObvious999 wrote:Couldn't they use the KDE API? Or would that make it impossible for Gnome to use?
Well, the KDE API is built on Qt
Both GNOME and KDE are under the GPL as far as I'm aware, some parts might be under the LGPL, because the LGPL is basicly a compromise between the BSD licensing philosophy and Richard Stallman's free software philosophy. The LGPL allows proprietary apps to link to it, so taht you can write proprietary apps using GTK without violating a license.
This is basicly a very smart trick by Trolltech, because by paying them for a commercial license of Qt you are allowed to bypass the GPL.