Techniques for Generation Digital elevation models

Any digital representation of the continuous variation of relief over space surface is known as Digital elevation model. DEM ‘s have been used and are currently in use in a great number of applications such as route engineering landspacing military -purpose mapping remote sensing telecommunications hydraulic studies land and geographic information systems. This research deals with study of different techniques for DEM generation. DEM definition was mentioned. The factors that affect in selecting a certain technique not the others then generation of DEM from topographic maps ground surveying (GPS) analytical photogrammetry digital photogrammetry and LIDAR was discussed.