QGIS Geographic Information System

This free open-source cross-platform desktop geographic information system (GIS) application supports viewing, editing, composing, and analyzing geospatial data. Originally developed by Gary Sherman in 2002, the project has grown into one of the most widely used open-source GIS platforms with over 10,000 stars as of 2026 and a global community of contributors. It is maintained under the auspices of the Open Source Geospatial Foundation (OSGeo). Key features include: multi-format data support (vector and raster formats including Shapefile, GeoPackage, PostGIS, GeoTIFF, WMS, WFS, WCS, WMTS, and XYZ tiles), cartography (advanced symbology, labeling, diagram overlays, rule-based rendering, 25D and 3D map views), spatial analysis (buffer, intersect, dissolve, clip, statistics, raster calculator, and terrain analysis), digitizing tools (advanced vertex editing, snapping, tracing, and topological editing), print composer (professional map layout creation with legends, scale bars, north arrows, attribute tables, and HTML frames), plugins (over 1,000 community plugins extending functionality for hydrology, network analysis, archaeology, and remote sensing), processing framework (integration with GRASS GIS, SAGA, OTB, GDAL, and R for hundreds of geoprocessing algorithms), Python console and PyQGIS API (full programmatic access for automation and custom tools), 3D map view (3D terrain visualization with textured meshes, point clouds, and 3D models), mesh layers (temporal mesh data for computational hydraulics and meteorology), and temporal controller (time-aware layers for animated temporal data visualization).