A Digital Elevation Model (DEM) is a raster representation of a continuous surface. It usually refers to the earth’s surface, using a set of points whose X, Y and Z values are known and defined in an arbitrary coordinate system (Fallas, 2007).
The information that can be derived from digital elevation models can be applied in different fields, such as hydrology, risk analysis, urban planning, among others. The main products that can be obtained from a DEM are slope maps, contours, relief maps, visibility maps, aspect maps, watersheds, viewshed, etc.
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