UTC
Coordinated Universal Time (UTC) is the international time standard used as the basis for civil time and time zones worldwide. It is based on atomic time and may be adjusted with leap seconds to account for Earth’s rotation.
On a leap-second day, the last minute can have 61 seconds. To keep UTC close to Earth’s rotation, clocks may insert 23:59:60 after 23:59:59. Because that extra second can disrupt computer systems, global timekeepers plan to change the system by 2035.
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