GRASS GIS (Geographic Resources Analysis Support System) is a free and open-source Geographic Information System (GIS) software suite utilized for geospatial data management and analysis, image processing, graphics and map production, spatial modeling, and visualization. It supports raster, vector, and geospatial processing, enabling advanced modeling, data management, imagery processing, and time series analysis with a Python API, optimized for large-scale analysis. GRASS GIS is compatible with multiple operating systems, including OS X, Windows, and Linux, and can be accessed through a graphical user interface or integrated with other software such as QGIS. The software includes over 350 modules for rendering maps and images, manipulating raster and vector data, processing multispectral image data, and creating, managing, and storing spatial data. GRASS GIS is widely used in academic and commercial settings, as well as by governmental agencies.