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Real-Time Clock (RTC)

Vangie Beal
Last Updated May 24, 2021 7:53 am

A clock that keeps track of the time even when the computer is turned off. Real-time clocks (RTCs) run on a special battery that is not connected to the normal power supply. In contrast, clocks that are not real-time do not function when the computer is off.

Do not confuse a computer’s real-time clock with its CPU clock. The CPU clock regulates the execution of instructions.