What is Dem?
A Digital Elevation Model (DEM) may be a specialized database that represents the relief of a surface between points of known elevation. By interpolating known elevation data from sources like ground surveys and photogrammetric data capture, an oblong digital elevation model grid is often created.
The slope is the steepness or the degree of incline of a surface. Slope can't be computed from the lidar points directly; one must first create either a raster or TIN surface. Then, the slope for a specific location is computed because of the maximum rate of change of elevation between that location and its surroundings. The slope can be expressed either in degrees or as a percentage.
Aspect is that the orientation of slope, measured clockwise in degrees from 0 to 360, where 0 is north-facing, 90 is east-facing, 180 is south-facing, and 270 is west-facing.
Hillshading may be a technique wont to visualize terrain as shaded relief, illuminating it with a hypothetical light. The illumination value for every raster cell is decided by its orientation to the sunshine source, which is predicated on slope and aspect.
Download Sikkim DEM file: click here
Download Sikkim Shapefile: click here