Are you finding that Google Earth is not filling your needs while professional geographic software packages are out of reach? Below are a few free open source GIS packages just added to the Element List database. For an exhaustive listing of free GIS software products, see also FreeGIS.org.
Geographic Resources Analysis Support System, known as GRASS GIS, is a product of the Open Source Geospatial Foundation. It was originally developed by the U.S. Army Construction Engineering Research Labs and is used for geographic data management, image processing, modeling, and visualization. It is free, open source software and works on Linux, Mac OS X, UNIX, and Windows operating systems.
PostGIS is an open source spatial database system developed by Refractions Research based in Canada. PostGIS works as a data source for many other open source GIS tools, including GRASS mentioned above. PostGIS is essentially a GIS add-on to the PostgreSQL database server.
Quantum GIS (QGIS) is designed to be a user friendly open source GIS that runs on Linux, UNIX, Mac OSX, and Windows and is written entirely by volunteers. QGIS coding officially began in 2002 and originally only supported PostGIS layers. The software has grown substantially to include a feature-rich graphical user interface (pictured above) and support for a wide range of data types.
