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 means height above the ground or above the sea level. Common uses include aviation (flying, parachuting, gliding), and geography / surveying. In geometry it is also used as the height of the object itself. Generally, altitude is the distance one thing is above another thing. This is in the vertical or up direction. For the height of the ground (such as for hills and mountains), the word elevation is also used and might be a better choice.