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Explain the following terms:Polling, Interrupt.

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Polling:
•Polling is the process where the computer or controlling device waits for an external device to check for its readiness or state, often with low-level hardware.
•For example, when a printer is connected via a parallel port, the computer waits until the printer has received the next character.
•These processes can be as minute as only reading one bit.

 Interrupt:
•An interrupt is a signal to the processor emitted by hardware or software indicating an event that needs immediate attention.
•An interrupt alerts the processor to a high-priority condition requiring the interruption of the current code the processor is executing.
•The processor responds by suspending its current activities, saving its state, and executing a function called an interrupt handler (or an interrupt service routine, ISR) to deal with the event.

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