What is Coordinated Universal Time (UTC)?

Coordinated Universal Time (UTC) is the primary time standard that the world uses to correctly regulate time and clocks. UTC makes use of extremely precise atomic clocks in conjunction with the Earth's rotation, and is always within one second of mean solar time at 0° longitude and is not adjusted for daylight savings time. UTC, which was implemented on January 1, 1960, is the successor to Greenwich Mean Time (GMT). UTC time is a critical data point used by investors as a universal indicator of the times that different stock markets open and close across the globe.