Commonly referred to as GRASS, this is free Geographic Information System (GIS) software used for geospatial data management and analysis, image processing, graphics/maps production, spatial modeling, and visualization. GRASS is currently used in academic and commercial settings around the world, as well as by many governmental agencies and environmental consulting companies. GRASS is an official project of the Open Source Geospatial Foundation.
The FreeGIS Project provides
software overview on Free Geographic Information Systems (our web site)
communication on developments, plans, infos on Free GIS Software and Free Geo-Data (our mailing list)
A Free and Open Source Geographic Information System
DIVA-GIS is a free computer program for mapping and geographic data analysis (a geographic information system (GIS). With DIVA-GIS you can make maps of the world, or of a very small area, using, for example, state boundaries, rivers, a satellite image, and the locations of sites where an animal species was observed. We also provide free spatial data for the whole world that you can use in DIVA-GIS or other programs.