What is GIS?

"Geographic Information Systems (GIS) represents a collection of computer hardware, software, and geographic data for capturing, managing, analyzing, and displaying all forms of geographically referenced information."

Three Views of GIS

I: The Spatial Database

A GIS is a geographic database (or geodatabase) of the world. "Fundamentally, a GIS is based on a structured database that describes the world in geographic terms."

II: The Map View

The Map View is based on Geovisualization, which refers to "working with maps and other views of the geographic information including interactive maps, 3D scenes, summary charts and tables, time-based views, and schematic views of network relationships."

III: The Model View

"A GIS is a set of information transformation tools that derive new geographic datasets from existing datasets. These geoprocessing functions take information from existing datasets, apply analytic functions, and write results into new derived datasets."

Source: Environmental Systems Research Institute (ESRI) 2007.