 Digital elevation models

Digital Elevation Models (DEMs) are 3D representations of a terrain's surface created from terrain elevation data. They are used to depict the Earth's surface in a digital format, showing elevation values at various points over a geographic area. DEMs can be generated from a variety of sources, including: 1. **Remote Sensing**: Techniques like LiDAR (Light Detection and Ranging) or satellite imagery can capture elevation data from above the Earth's surface.