Geographic Information System http://en.wikipedia.org/wiki/Geographic_information_system http://en.wikipedia.org/wiki/Geographic_information_system "A geograph

Geographic Information System http://en.wikipedia.org/wiki/Geographic_information_system http://en.wikipedia.org/wiki/Geographic_information_system "A geographic information system is a system designed to capture, store, manipulate, analyze, manage, and present all types of geographically referenced data." Open Source: Quantum GIS http://www.qgis.org/ http://www.qgis.org/ and GRASS http://www.osgeo.org/grass http://www.osgeo.org/grass are good places to start.