A geographic information system (GIS) is a computer
system capable of capturing, storing, manipulating,
and displaying spatially referenced information. GIS
is a tool for planning and decision making processes.
GIS is used in a wide range of applications including
urban and regional planning, agriculture, emergency
response systems, and natural resource management.
GIS enables users to produce high quality maps at any
scale, to store and maintain a large quantity of geographically
related information, to visualize and simplify complex
data, and to create new data from existing data. The
most powerful aspect of a GIS is that it allows users
to perform complex analyses by linking data layers and
overlaying different data sets to get a spatial perspective.