UTC, basis for uniform calculation of time in all parts of the world that is based on the atomic clock (method that is more modern and precise than GMT)
Coordinated Universal Time (UTC) is a high-precision atomictime standard. UTC has uniform seconds defined by International Atomic Time (TAI), with leap seconds announced at irregular intervals to compensate for the earth's slowing rotation and other discrepancies. Leap seconds allow UTC to closely track Universal Time (UT), a time standard based not on the uniform passage of seconds, but on the Earth's angular rotation.
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