I am relatively new to Linux and Ubuntu. I have attached the system monitor to the bar (the upper bar of the screen) and opened the preference to configure this gadget. On the processor tab I see that I can mark the choose 5 colors : user, system, nice, IOwait and idle. I can understand all 4 (I think...) except for "nice". What is this "nice" ? I read this answer and I understand that the superuser can perform tasks with greater priority but , what does it mean if I see it in the system monitor without me running any new nice processes ?