OS App relations. Do they relate? How do they relate?

The user uses the App to talk to the machine.

The app passes on messages to the OS

The OS talks to the hardware and also passes on the messages. "Hey do this, do that" to the outputs. I.e. Printer, mouse, keyboard etc.

The user says "print" to the app(s), thew app(s) says "print" to the app(s) and the printer says "print" to the printer

Printer problems for practical

Paper out - No paper in the paper tray, put paper into tray.
How do I fix it? - Pick up a pile of A4 sheets, and insert into printer tray
Paper jam - Open up printer and feed out paper. (Don't rip)
 How do I fix it? - Basic. Open up the printer, though the back latch on most conventional printers, and slowly and carefully weave you hand though and slide it out. 
Load A4 paper - In a multiple-paper printer (A3,A4 etc.) It needs more A4 paper in the tray.
How do I fix it? -  So easy. Basically the same as No.1. Just find the right place it's supposed to go, and place it in. :)

Printer offline - It is not connected to any computers/wireless (WiFi) devices. It's sleeping...
How do I fix it? - Not too tricky, but just go into file, then print, or command P. and sync with the printer.

Sounds quite simple in this context... Am I right? Hmmmmmm.

Information from myself and party from Mr Wells

-Paddy Foss