Profile is a set of paramter setting that can be used to fine tune your project rapidly.
The profile is made of three part,print settings profile,filament settings profile and printer settings profile.
There is two kind of profile defined in the QIDISlicer.
System profile comes with the Software,we can access and select them in the way shown in the below instruction.
After select some specific profile,setting on that profile would apply to next print.
In most instances,system profile is enough,we can just select some existing system profile according to your actual situation,but in certain cases,system profile may not run very well,it's time for us to adjust our setting and further more save our setting as user profile for next similar cases.
You can follow instruction below to add a new profile