Time Zone

The time zone map

Below is the complete map with which to retrieve the different time slots.

Exact time of the main cities of the world

What is the time zone and why we have them

The time zone definition start from the assumption that the earth has a spherical shape and that a complete rotation of 360 degrees on its own axis takes place in 24 hours; dividing grades for the hours we get 24 cloves of angular amplitude of 15 degrees; that path is then traveled in one hour.
The time zone is no more than the clove, or rather the time only applied to the wedge, in the defining of time is used that has the meridian passing through the center of the segment of 15 degrees.

So we have a total of 24 time zones and always by convention are indicated in relative terms with reference to the prime meridian of longitude 0 passing through the Greenwich Observatory, London in England, who is called GMT (Greenwich Mean Time).

Over time it has been replaced by UTC (Coordinated Universal Time), which coincides with the GMT but it was decided to remove the name of a place from a value international standard.

Thanks to the time zone time varies from one country to another in multiple of time moving from one meridian to another, if we go from East to West we will turn back the clock as many hours as the number of time zones, vice versa traveling from west to east.

It must be said that the allocation of time zone also follows political/economic choices and therefore there are cases in which the time zone of a country does not follow perfectly the clove physical defined by meridians, one example are Spain and France that have the same time zone of Italy although not belong to the same longitudinal band, the reason is to facilitate trade relations between countries. Even more extreme is the choice of China that uses a single time zone.

When traveling to another country you also have to pay attention must be taken over to the time zone of arriving to the presence of daylight saving time (both the country of departure to arrival).

The acronyms UTC, PST, MST, CST, EST, CET

Traveling is important to know the acronyms related to time zones, nothing complicated, they are an alternative way to express the time in relation to UTC, the time reference standard previously seen.

The most important symbols to be known are those used in the United States, let's have a look to them starting from the west to the east and also considering the time difference with UTC (similar to the difference with United Kingdom):

• PST - il Pacific Standard Time equal to UTC - 8, this is the time that we find in the Pacific coast of the United States, but also in some areas of Canada and Mexico
• MST - Mountain standard time equal to UTC - 7 , is the time of the mountainous areas in the west of the United States
• CST - Central standard time equal to UTC - 6, are the areas in the middle of the United States, on this zone are also Canada, Mexico, Guatemala, Honduras, etc ..
• EST - Eastern standard time equal to UTC - 5, is the time of the East Coast of the United States, the time in New York and other South American countries such as Peru, Cuba, Ecuador, etc ..

Il CET (Central Europe Time) it is the Central European Time and is equivalent to UTC + 1 it includes all the countries like Italy, France, Germany, etc ...