The modern computer is an interrupt-based machine.

A processor can only accept interrupts from a single source.

When an interrupt occurs the contents of the processor registers are lost.

The interrupt vector is a pointer to the first instruction that should be executed in the interrupt service routine.

A lower priority interrupt can usually interrupt a higher priority interrupt.

Multiple interrupts are handled by an interrupt controller.

The hard disk is able to generate interrupts.

When an interrupt occurs, processor registers are saved on the stack.

There are no latencies associated with the handling of interrupts.

The interrupt service routine cannot be relocated within the processor’s address space – it has to be at a fixed location.