IT all started in early when transportation and communication were developing; the coordination of different areas was a real mesh. For example, if there was noon in any place in the west, whereas in the south, the afternoon was almost over, and it created a lot of problems among the USA railway officers and the officers who were working in the expansion of the railway run.
So, to face the situation, the standard system was recommended in Whereas, some intellects also propose that the GMT concept was introduced in where 26 countries held a meeting and came to the solution that the royal observatory in Greenwich London will be taken as the reference point as 0-degree longitude. The above concepts suggest the same theory that the globe is divided into 24 time zones. According to theory, our earth completes one rotation in its axis in 24 hours that equal to degrees in 1 rotation.
From the North pole to the South pole, 24 lines were drawn at an interval of 15 degrees each. So, the earth moves 15 degrees in an hour.
Mariners from other countries later adapted this practice which led to the use of GMT as a worldwide reference for time zones in different parts of the world. It uses two different conventions for numbering hours. One convention refers to noon as zero hours based on the work of Ptolemy. This led to the creation of a fictitious mean sun which is the annual average of the uneven motion of the sun, thus the name Greenwich Mean Time.
The other is the civil convention which refers to midnight as zero hours which is based on the practice of the Romans.
It was introduced and became very popular in the early s. Its use starts at the onset of the summer months which begins on the last Sunday of March and ends on the last Sunday of October. It was meant as a daylight savings time adding an hour to GMT to make use of the extended daylight of summer.
For two years it was adapted by the United Kingdom as their standard time but was later reverted to summer time because of an increase in accidents during the day. Difference Between Similar Terms and Objects. MLA 8 M, Emelda. In daylight savings, the clocks are adjusted forward one hour near the start of spring and are adjusted backward in autumn. Daylight saving time is also called summer time in several countries, such as in Britain, and other European countries.
This is done so that the citizens may get more hours of daylight during the day, and hence use less artificial methods of lighting during the evening. In , it will begin on 31 March and end on 27 October. Image Courtesy: freelights.
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