This technique is used to overcome the limitation of programmed I/O.
In interrupt driven I/O, instead of making the processor to verify the status of I/O module. It is the responsibility of I/O module to intimate the processor by interrupt signal.
CPU responds to interrupt signals and stores the return address from the program counter (PC) into the memory stack and then the control branches to a interrupt service routine (ISR).
ISR processes the required I/O Transfer.
After completion of executing interrupt routine CPU returns to previous program and continue what it was doing before.
Interrupt:
An interrupt or exception causes CPU to transfer the control temporarily from its current program to another program i.e. interrupt handler.