WGS84

WGS84 is the acronym of World Geodetic System 1984 and defines the system like geodetic, world-wide, reported to 1984.

It constitutes a mathematical model of the Earth from a geometric, geodetic andgravitational point of view , constructed on the base of the measures and the scientific and technological acquaintances available to 1984.
The datum of classic geodesy, that they can be defined local or regional, approximates the single geoide well in around of the emanation point, while total datum WGS84 uses standard EGM96, that it approximates the geoide in its complex and is valid all over the world.

From 2000 it is obligatory I use it of the WGS84 like standard for the air navigation. In Italy however it is still in course (the 2005) conversion of the aeronautical data ofthe ENAV from old standards ED50 and MM40 to the WGS84, whilethe Italian Air Force has finished the conversion in 2002.