Inter-processor interrupt

Inter-processor interrupts are a way for two computers to communicate with each other. Imagine if you wanted to ask your friend to do something. You could call your friend on the phone and ask them to do it. In the same way, when two computers want to communicate with each other, they can use inter-processor interrupts. When one computer sends an inter-processor interrupt to another computer, it's like the first computer is picking up the phone and asking the second computer to do something. The second computer then responds to the request, and they can communicate with each other in this way.