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This is a list of time zone abbreviations.
Time zone
A time zone is an area which observes a uniform standard time for legal, commercial and social purposes. Time zones tend to follow the boundaries between countries and their subdivisions instead of strictly following longitude, because it ...
s are often represented by alphabetic abbreviations such as "EST", "WST", and "CST", but these are not part of the international time and date standard
ISO 8601
ISO 8601 is an international standard covering the worldwide exchange and communication of date and time-related data. It is maintained by the Geneva-based International Organization for Standardization (ISO) and was first published in 1988, w ...
and their use as sole designator for a time zone is discouraged. Such designations can be ambiguous; for example, "CST" can mean
China Standard Time
The time in China follows a single standard time offset of UTC+08:00 (eight hours ahead of Coordinated Universal Time), even though the country spans almost five geographical time zones. The official national standard time is called ''Beijing T ...
(UTC+8),
Cuba Standard Time (UTC−5), and (North American)
Central Standard Time (UTC−6), and it is also a widely used variant of ACST (
Australian Central Standard Time, UTC+9:30). Such designations predate both ISO 8601 and the internet era; in an earlier era, they were sufficiently unambiguous for many practical uses within a national context (for example, in railway timetables and business correspondence), but their ambiguity explains their deprecation in the internet era, when communications more often cannot rely on implicit geographic context to supply part of the meaning.
See also
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List of tz database time zones
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List of military time zones Military time zones are defined in the ACP 121(I) standard, which is used by the armed forces for Australia, Canada, New Zealand, the United Kingdom, the United States, and many other nations. The names are identical to the NATO phonetic alphabet. ...
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Lists of time zones
International:
* List of time zones by country – sorted by number of current time zones in the world
* List of UTC time offsets – current UTC offsets
* List of time zone abbreviations – abbreviations
* List of tz database time zones – zon ...
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Time zone abolition
The abolition of time zones involves replacing time zones with Coordinated Universal Time (UTC) as a local time.
History
For most of part of history, the position of the sun was used for timekeeping. During the 19th century, most towns kept t ...
References
Notes
External links
Greenwich Mean Time (GMT) :: UTC :Time Zone Abbreviations
{{UTC time offsets
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