Line or line the International time (IDL) is linear hypothetical on the surface of the earth, that from the middle of the Pacific Ocean, passes, and ships and planes, with the passage of this line, the date, the day on which the overcrowded to change.

line to be somewhat aligns with the orbit of the meridian of 180 degrees (the point opposite the meridian of origin), but in parts of the circuit, drifts can be divided when some units and political groups in the island to prevent.

from longitude up line in the direction of the East, 180 degrees east (E) and in the direction of West to 180 degrees west (W) is divided.

when crossing the line from West to East should be a day to the calendar, adding to the picture when crossing from East to West, this line should be a day of the calendar. Countries located in the east of this line, the Western countries compared to the meridian of Greenwich (Western Hemisphere), and Western countries. the countries of East relative to the Meridian Greenwich (hemisphere Oriental) poses come.

if a passenger from the West, Earth to the east (from continental US to continental Asia) is a time the earth away in vain. one day calender from Origin, your move, can happen and should be a day to date ' and, on the contrary, from east of Earth to West ( from Asia to the US) should be one day from the date.