Writing, developed first by people in Sumer, is considered a hallmark of civilization and appears to accompany the rise of complex administrative bureaucracies or the conquest state. Traders and bureaucrats relied on writing to keep accurate records.
Elevation, or geometric height, is mainly used when referring to points on the Earth 's surface, while altitude or geopotential height is used for points above the surface, such as an aircraft in flight or a spacecraft in orbit, and depth is used for points below the surface. topographical map is the main type of map used to depict elevation, often through use of contour lines. In a Geographic Information System (GIS), digital elevation models (DEM) are commonly used to represent the surface (topography) of a place, through a raster (grid) dataset of elevations.
altitude, height-elevation especially above sea level or above the earth's surface; the altitude gave her a headache. ground level, grade-the height of the ground on which something stands; the base of the tower was below grade. water level-the level of the surface of a body of water.. the height to which something is elevated or to which it rises. 3. the altitude of a place above sea level or ground level. 4. an elevated place; eminence. 5. a drawing that represents a building or other object as being projected geometrically on a vertical plane parallel to one of its sides.