I have been lucky when I have done my choices as I have not used SQL Server Agent since 2 years.But after 5 minutes , I have done my choice as I was remembering only for these 2 parameters.
Anyway , after having validated my choices , I hurried on the provided link and I got more explanations.
I think I will have to restart to use SQL Server Agent , maybe next week.
Now , I am too busy after my upgrade from Windoxs 8.1 upto Winows 10 ( 7 hours )
Anyway , an useful question as I had to dig in the depth of my own memory.
So , thank you very much.