UTC breaks time into days, hours, minutes, and seconds, where days are usually defined in terms of the Gregorian calendar. Time zones throughout the world vary, and used to vary even more than they currently do. Russia on the other hand, is divided into 11 time zones, though at one point this was reduced to 9 time zones. As can be seen, although there is a general standard throughout the world for defining time zones, it is still highly dependent on the country, and is subject to change.
The following map displays the standard time zones across the world. Click the map to enlarge it. Many countries have more than one time zone. In the U. These time zones encompass most of the contiguous United States. Many countries or regions, especially those in Europe and North America, practice daylight saving time DST , sometimes referred to as "summer time," with the intent of saving energy.
This typically involves advancing the time on a clock by one hour in early spring, and "rolling back" the time in autumn. The United States , for example, contain twenty-nine time zones. Why do we have time zones? The use of time zones makes it easier for us to organise our lives, from commercial operations up to traveling. People living within the same time zone know that they will be working at the same time, while someone in another time zone will work based on the local time of his or her own time zone.
Time has traditionally been measured according to the position of the sun in the sky, which is different depending on where you are in the world. In the nineteenth century, when mechanical clocks began to become popular, time was calculated locally. Since the time calculations were based on the position of the sun, they could vary by four minutes for each degree of longitude.
A better system was required to enable an efficient operation of railways and new telecommunication systems.
Other countries created their own standard times and, in the late s, the International Meridian Conference proposed a standardised hour day, starting off at midnight GMT. Eventually the rest of the world began to use this system, shaping the time zones we know today.
The Daylight Saving Time is used by many countries during the summer, including the United Kingdom , Germany , Holland , Spain and France and in most American States , so that it is longer daylight in the evenings and longer dark in the mornings.
In regions that are using Daylight Saving Time the clocks are typically moved forward by one hour at the beginning of the spring and moved back again by an hour in autumn. The system, which is usually attributed the English-born astronomer and entomologist George Vernon Hudson, was first introduced in Germany during World War I to save coal by requiring less light in the evening.
Other countries, including the UK, soon followed Germany. Standard time is the name used for the uniform time created by the synchronization of all clocks within a time zone.
Standard times are shown as positive or negative deviations of UTC, that's why time differences are calculated by determining UTC and calculating each time zone from there. If applicable, differences to standard times as a result of DST also need to be taken into account.
The simplest way to figure out the time in another part of the world is to make use of this website. It will help you to discover what cities are in which time zones and it will give you the standard times within each time zone. Furthermore, it will do time difference calculations for you. New York. Hong Kong. Time Zone Converter Time Difference Calculator Compare the local time of two timezones, countries or cities of the world.
Look up the current local time and the date Simply enter any place, country or time zone and figure out the current local time with its corresponding date. Identify the time difference between two cities or countries Calculate the time difference between two places with the time zone calculator. Compare the local time of two world cities Tabular comparison of two local times, e.
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