The concept of “time of day” was invented thousands of years ago, when societies had to keep track of how long it had been since sunrise, how much time of day light they still had left, etc. Our modern “hours” come from the Middle East (Sumer, if I recall correctly) where they came up with the idea of dividing the day time into two halves: before noon and after noon, and each half had 6 hours. The 12 hours of night were added later.
This system spread all over the world in the following millenia, with modifications, of course, like dividing the hours in 60 minutes, making them all last the same amount of time, etc. But the constant that remained was “noon” as the dividing point of the day. Noon is when the Sun is highest in the sky, but because the Earth is a sphere that doesn’t happen at the same time everywhere. Say that it’s noon right now where you live, for places in the east the Sun will have already move past noon, while places in the west are still before noon. Only in places directly north and south it’s noon at the same time.
Back in the good old days people adjusted their watches (actually it was more likely the main tower clock) to the noon in the place they lived, which meant that every town and city had their own time. No one cared because the fastest you could get from one place to the other was by train or horse and the difference of a few minutes was not important.
When communications became electronic suddenly it started to matter. It was difficult to coordinate timetables, agree on when things had to be done, and when something had happened when every town had its own time. So, in the interest of commerce and communications the United States asked all the other countries to come together and think of a way to standardize time. In the International Time Meridian conference of 1884 everybody agreed to use the Greenwich Meridian as the Prime Meridian, and to divide the world in time zones determined from this Prime Meridian.
So, in a way time is the same for all countries in the world, since officialy all times have a UTC (Universal Time Coordinated) equivalency, even if they use a different Local Time (offset from the UTC).
Sometime you will hear the the official time in some place is +6 or -7 or something like that. That’s how many hours you need to add or subtract from the UTC to get the local time in that place. For example, in the Summer New York City is at -4, so if UTC is 1500 (3:00PM) we subtract 4 hours to get the time in NY: 1100 (11:00AM).
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Answer:
Explanation:
The concept of “time of day” was invented thousands of years ago, when societies had to keep track of how long it had been since sunrise, how much time of day light they still had left, etc. Our modern “hours” come from the Middle East (Sumer, if I recall correctly) where they came up with the idea of dividing the day time into two halves: before noon and after noon, and each half had 6 hours. The 12 hours of night were added later.
This system spread all over the world in the following millenia, with modifications, of course, like dividing the hours in 60 minutes, making them all last the same amount of time, etc. But the constant that remained was “noon” as the dividing point of the day. Noon is when the Sun is highest in the sky, but because the Earth is a sphere that doesn’t happen at the same time everywhere. Say that it’s noon right now where you live, for places in the east the Sun will have already move past noon, while places in the west are still before noon. Only in places directly north and south it’s noon at the same time.
Back in the good old days people adjusted their watches (actually it was more likely the main tower clock) to the noon in the place they lived, which meant that every town and city had their own time. No one cared because the fastest you could get from one place to the other was by train or horse and the difference of a few minutes was not important.
When communications became electronic suddenly it started to matter. It was difficult to coordinate timetables, agree on when things had to be done, and when something had happened when every town had its own time. So, in the interest of commerce and communications the United States asked all the other countries to come together and think of a way to standardize time. In the International Time Meridian conference of 1884 everybody agreed to use the Greenwich Meridian as the Prime Meridian, and to divide the world in time zones determined from this Prime Meridian.
So, in a way time is the same for all countries in the world, since officialy all times have a UTC (Universal Time Coordinated) equivalency, even if they use a different Local Time (offset from the UTC).
Sometime you will hear the the official time in some place is +6 or -7 or something like that. That’s how many hours you need to add or subtract from the UTC to get the local time in that place. For example, in the Summer New York City is at -4, so if UTC is 1500 (3:00PM) we subtract 4 hours to get the time in NY: 1100 (11:00AM).