Virtually all computers provide a mechanism by which other modules (I/O, memory) may interrupt the normal sequencing of the processor.
Interrupts are provided primarily as a way to improve processor utilization.
With interrupts, the processor can be engaged in executing other instructions while an I/O operation is in progress.
When the external device becomes ready to be serviced, that is, when it is ready to accept more data from the processor, the I/O module for that external device sends an interrupt request signal to the processor. The processor responds by Suspending operation of the current program; branching off to a routine to service that particular I/O device, known as an interrupt handler; and resuming the original Execution after the device is serviced.
IN MICROPROCESSORS:-
Interrupt is the method of creating a temporary halt during program execution and allows peripheral devices to access the microprocessor. The microprocessor responds to that interrupt with an ISR (Interrupt Service Routine), which is a short program to instruct the microprocessor on how to handle the interrupt.
