The concept of legal time refers to the establishment of an hour given by the administration or government of a given country. It may apply to the whole country or to a part of it in the case of large territories in the sense of geographical length (Russia, the United States, etc.). It corresponds to what is known as local time, although there is a difference between the two concepts that can be important in some occasions: the local time when we fly over one of the great oceans is the one that corresponds to the geographical longitude to which the plane (or the ship in the case of maritime navigation) while the legal time refers to the one that each state establishes in its territory to govern daily life in it.

Legal time is based on a meridian and not a time zone. Therefore it is that to establish the time of a time zone as the one that determines the central meridian of the same one (as it is established in the article on the time zones and in the one of the international line of date change) has turned out to have no utility in practice. Bibliography

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