A geographic information system (GIS) is a computer system designed to capture, store, manipulate, analyze, manage, and present all types of geographical data. GIS can be thought of as a system that provides spatial data entry, management, retrieval, analysis, and visualization functions. GIS applications are tools that allow users to create interactive queries (user-created searches), analyze spatial information, edit data in maps, and present the results of all these operations. GIS is the science underlying geographic concepts, applications, and systems.
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