IDL


 * IDL **

The International Date Line (IDL), is an imaginary line which runs roughly along the 180° line of longitude, in the middle of the Pacific Ocean. International convention accepts the International Date Line as the location where one day is divided from the next, with the area in the Eastern Hemisphere one day ahead of the Western Hemisphere. This line is necessary to address certain oddities which occur during travel; people going all the way around the world perceive themselves either gaining or losing a day, depending on which direction they travelled in.


 * //How Time Zones Work//**

In theory, the world could be divided up into 24 time zones, one for each hour of the day. Time zones are actually set by each country independently, however, and local time does not necessarily match these ideal standard time divisions. Ideally, the time zones are designed so that local noon falls when the sun is roughly overhead. Travelling west, a person would lose an hour for every 15° of longitude; while travelling east, towards the sun, he or she gains an hour.

The location of the International Date Line was chosen because it is in a relatively uninhabited area of the Pacific. The presence of inhabited areas, including Alaska, Russia, and a number of islands , mean that the line deviates in some areas. If the line was straight, the eastern most part of Russia would be a day behind the rest of the country, while a number of islands that are part of Alaska would be a day ahead of the state. This would likely result in confusion and administrative chaos.
 * //How the IDL Location Was Chosen//**