MASTERCLOCK
Master clock
A master clock is a precision clock that provides timing signals to synchronize slave clocks as part of a clock network. Networks of electric clocks connected by wires to a precision master pendulum clock began to be used in institutions like factories, offices, and schools around 1900. Today many quartz clocks are synchronized by radio signals or internet connections to a worldwide time system called Coordinated Universal Time which is governed by master atomic clocks in many countries.The above text is a snippet from Wikipedia: Master clock
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