ABSTRACT
Geographical (or geographic) information can be defined as information about features and phenomena located on or near the surface of the Earth (Goodchild et al., 1999). Geographical information arises mainly from the practical need to solve geographical problems, some of which are indeed very pressing, being of major environmental and social concern, such as biological conservation, or of an immediate nature, such as finding a route for a trip. The gathering of geographical information is undertaken by government agencies such as the United States Geological Survey and the Ordnance Survey of Great Britain, and by various private sector companies.
