Definition: interrupt

A signal that gets the attention of the CPU and is usually generated when I/O is required. For example, hardware interrupts are generated when a key is pressed or when the mouse is moved. Software interrupts are generated by a program requiring disk input or output.

An internal timer may continually interrupt the computer several times per second to keep the time of day current or for timesharing purposes.

When an interrupt occurs, control is transferred to the operating system, which determines the action to be taken. Interrupts are prioritized; the higher the priority, the faster the interrupt will be serviced.