Standard time is the result of synchronizing clocks in different geographical locations within a time zone to the same time rather than using the local meridian as in local mean time or solar time. The time so set has come to be defined in terms of offsets from Universal Time. (See more about standard time.) A time zone is a region of the Earth that has adopted the same standard time, usually referred to as the local time. ... Local mean time is a form of solar time that corrects the variations of local apparent time. ... Solar time is based on the idea that when the sun reaches its highest point in the sky, it is noon. ... Universal Time (UT) is a timescale based on the rotation of the Earth. ... Universal Time (UT) is a timescale based on the rotation of the Earth. ...

Where daylight saving time is used, standard time may refer to the time without daylight saving time. Though DST is common in Europe and North America, most of the worlds people do not use it. ...

History of Standard Time

Great Britain

Standard time was first used by British railways on December 11, 1847, when they switched from local mean time to GMT. The vast majority of Great Britain's public clocks were being synchronised using GMT by 1855. December 11 is the 345th day of the year (346th in leap years) in the Gregorian calendar. ... 1847 was a common year starting on Friday (see link for calendar). ... For alternate meanings of GMT, see GMT (disambiguation). ...

North America

Prior to the 1883, local mean time was used throughout North America, resulting in an inordinate number of local times. This caused convoluted regional and national train schedules. Sandford Fleming, a Canadian, proposed Standard Time at a Meeting of the Royal Canadian Institute on 1879 February 8. The heads of the major railroads met in Chicago to adopt the Standard Time System. The new system was adopted by most states almost immediately after railroads did so and finally officially adopted by the U.S. government almost fifty years later. Sir Sandford Fleming Sir Sandford Fleming (January 7, 1827 – July 22, 1915) was a prolific Canadian engineer and inventor, known for the introduction of Universal Standard Time, Canadas first postage stamp, a huge body of surveying and map making, engineering much of the Intercolonial Railway and the Canadian Pacific... 1879 (MDCCCLXXIX) was a common year starting on Wednesday (see link for calendar). ... February 8 is the 39th day of the year in the Gregorian calendar. ... Nickname: Motto: Urbs In Horto (Latin: City in a Garden), I Will Location in the Chicago metro area and Illinois Coordinates: , Country United States State Illinois County Cook & DuPage Settled 1770s Incorporated March 4, 1837 Government  - Mayor Richard M. Daley (D) Area  - City  234. ...

See also

• Solar time
• Time zone
• Universal Time

Solar time is based on the idea that when the sun reaches its highest point in the sky, it is noon. ... A time zone is a region of the Earth that has adopted the same standard time, usually referred to as the local time. ... Universal Time (UT) is a timescale based on the rotation of the Earth. ...

References

Further reading

• Ian R. Bartky (1989-01). "The adoption of standard time". Technology and Culture 30 (1): 25-56. 
• Eviatar Zerubavel (1982-07). "The standardization of time: a sociohistorical perspective". The American Journal of Sociology 88 (1): 1-23.