[Qt-interest] What's the difference between a .pro and a .pri file?

[Malte Witt]

> ...and how (why) do you create a .pri file?

.pri is just an include file for .pro files. I guess the extension means 
"PRoject Include". You create it just like .pro files - no difference.
In your profile you can use the include()-statement to include any .pri.
This way you can out-source global settings and include them in different 
subprojects :-)

Regards,
Malte