A signal, generated by a source such as an input or output device or a systems software routine, which causes a break in the execution of the current routine. Control passes to another routine in such a way that the original routine can be resumed after the interrupt. This enables peripherals to operate independently, indicating to the operating system, with an interrupt, when they need to communicate with the central processor. An example is a keyboard, which only sends data to the central processor when a key is pressed, which generates an interrupt.