NMI
Updated: 12/31/2022 by Computer Hope
Short for Non-Maskable Interrupt, NMI is the highest priority interrupt capable of interrupting all software and non-vital hardware devices. The NMI is not commonly used except to detect if a serious error has occurred or stop all operations because of a failure. For example, when you press Ctrl+Alt+Del, when the computer freezes or stops responding, an NMI is sent to the CPU (Central Processing Unit).
Tip
Unlike an INTR (interrupt), the NMI cannot be interrupted by any other interrupt.