The Geographic Resources Analysis Support System, commonly referred to as GRASS GIS, is a GIS used for data management, image processing, graphics production, spatial modeling, and visualization of raster, vector and sites data. It is open source Free Software released under the GNU General Public License (GPL).
The new features of GRASS 6 cover a new topological 2D/3D vector engine and support for vector network analysis. Attributes are now managed in an SQL-based DBMS. A new display manager has been implemented. The NVIZ visualization tool was enhanced to display 3D vector data and voxel volumes. Messages are partially translated (i18N) with support for FreeType fonts, including multibyte Asian characters. New locations can be auto-generated by EPSG code number. GRASS is integrated with GDAL/OGR libraries to support an extensive range of raster and vector formats, including OGC-conformal Simple Features.