Editing Coordinated Universal Time

'''Coordinated Universal Time''' ('''UTC''') is the primary time standard used to regulate clocks and coordinate time worldwide. It is the reference for time-zone offsets (for example, UTC+1) and is widely used in aviation, navigation, computing, telecommunications, and scientific contexts.

UTC is based on highly stable atomic timekeeping and is kept close to Earth's rotational time. In practice, UTC provides a single, shared reference that allows systems and records in different regions to use consistent timestamps.

== Overview ==
UTC is used as a baseline from which local time zones are defined. Local time is commonly expressed as an offset from UTC (for example, ''UTC−5'' or ''UTC+9''). Many systems store and exchange timestamps in UTC to avoid ambiguity caused by time-zone changes and daylight saving time.

UTC is also used for standardized timestamps in:
* technical logs and system events
* transportation schedules and operations
* scientific measurements and datasets
* coordinated communications across regions

== Relationship to other time scales ==
UTC is related to, but distinct from, several other time scales:
* '''TAI''' (International Atomic Time) is a continuous atomic time scale without leap seconds.
* '''UT1''' is based on Earth's rotation and varies slightly due to irregularities in rotational speed.
* '''GMT''' (Greenwich Mean Time) is a historical time reference often used informally; in modern practice, UTC is the standard used for most civil and technical purposes.

== Leap seconds ==
UTC may occasionally be adjusted by a '''leap second''' to keep it within a close tolerance of Earth's rotational time. Leap seconds are inserted or removed at the end of a day as defined by international timekeeping authorities. Not all technical systems handle leap seconds in the same way, so implementations may document how leap seconds are represented in logs and time synchronization.

== Usage on this wiki ==
This wiki uses UTC as a neutral reference for timestamps where a single global standard is needed, especially for:
* release and revision timestamps
* chronological ordering across pages
* technical documentation involving logs, systems, or coordinated operations

Local times (including daylight saving time conventions) may be shown on pages where relevant, but UTC is preferred for cross-regional clarity.

== See also ==
* [[Time zone]]
* [[Greenwich Mean Time]]
* [[Daylight saving time]]
* [[Technical documentation]]

[[Category:Time standards]]
[[Category:Time]]
[[Category:Technical documentation]]
[[Category:Reference pages]]