a network of surveyed and monumented points on the earth's surface whose locations are established in accordance with national accuracy standards. A state plane coordinate system comprises a system of x, y coordinates for each state and is commonly used in GIS.
A network of carefully measured points that can be used as a reference for other surveys or to establish or measure accuracy in map making. Horizontal control and vertical control networks are typically separate because the former is based on an ellipsoid model of the earth, while the latter is based on a geoid model. See Also: ellipsoid, geoid More information on Geodetic Control.
A system of horizontal and/or vertical stations tied into horizontal and/or vertical datums, which are established to facilitate the location of other features on, above or below the earth's surface (see Datum).