What technique is used by GIS software to analyze elevation data?

The technique used by GIS software to analyze elevation data is Digital Elevation Models (DEMs). DEMs are a type of raster data that represent the Earth's surface's elevation. They provide a grid-based representation where each cell contains a value indicating the elevation at that point. This allows for various analyses, such as terrain modeling, hydrological analysis, and slope and aspect calculations.

DEMs are particularly significant in GIS because they facilitate the understanding of landscape features and the development of 3D visualizations of terrain. They help in assessing environmental impacts, planning infrastructure, and managing natural resources by providing accurate elevation information.

Other options, while relevant to GIS or data visualization, do not represent the specific technique for analyzing elevation data. D3.js is primarily a data visualization library used to create dynamic graphics and is not directly focused on elevation analysis. Geographical rastering is a general term that does not specifically address elevation. Rectangular coordinate systems are mathematical frameworks for defining locations, but they do not inherently analyze elevation.