Duplicate file save at end of session?

When I'm done with a Turbo Tax session I click on File then Save to ensure my changes are saved.  However when I then immediately select Exit (the program) it asks me if I want to save the file before exiting. Am I duplicating my effort here, can I just do one or the other and my changes will be saved?  I've noticed in my Turbotax file there are two copies, one with the tilda and one without.  Have I actually been creating two copies by my saving twice?