simply sequences of symbols that may be further interpreted formally. A datum is an individual value in a collection of data. Data is usually organized...

geodetic datum or geodetic system (also: geodetic reference datum, geodetic reference system, or geodetic reference frame) is a global datum reference...

standards, also includes a choice of geodetic datum (including an Earth ellipsoid), as different datums will yield different latitude and longitude values...

In geodesy, surveying, hydrography and navigation, vertical datum or altimetric datumis a reference coordinate surface used for vertical positions, such...

A datum reference or just datum (plural: datums) is some important part of an object—such as a point, line, plane, hole, set of holes, or pair of surfaces—that...

An ordnance datum (OD) is a vertical datum used by an ordnance survey as the basis for deriving altitudes on maps. A spot height may be expressed as above...

the large geodetic systems, such as European Datum (ED50), North American Datum (NAD), and Tokyo Datum (TD), to provide a worldwide geo-data basis Need...

The North American Vertical Datum of 1988 (NAVD 88) is the vertical datum for orthometric heights established for vertical control surveying in the United...

heights. A chart datum is generally derived from some tidal phase, in which case it is also known as a tidal datum. Common chart datums are lowest astronomical...

The North American Datum (NAD) is the horizontal datum now used to define the geodetic network in North America. A datum is a formal description of the...