Interrupt
In plain terms
A signal that diverts the CPU to handle an urgent event.
Going deeper
An interrupt pauses normal execution so the CPU can respond to hardware or software events immediately, then resumes. It enables responsive, event-driven systems.
Under the hood
Interrupt handlers (ISRs) must be fast; hardware interrupts (keyboard, timer) and software interrupts differ.
Examples
Keyboard input, timers, hardware events, I/O completion, ISRs.
Think of it like...
Like a phone ringing that makes you pause your work to answer.