Websites such as Wikimapia and OpenStreetMap are empowering citizens to create a global patchwork of geographic information while Google Earth is encouraging individuals to develop appplications using their own data.
The author of the paper (Goodchild MF (2007). Citizens as sensors: the world of volunteered geography. GeoJournal) concludes:
….collectively volunteered geographic information represents a dramatic innovation that will certainly have profound impacts on geographic information systems and more generally on the discipline of geography and its relationship to the general public.
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