A Geographic InformationSystem(GIS) integrates hardware,software,& data for capturing,managing,analysing,&displaying all forms of geographically referenced information. GIS allows us to view,understand,question,interpret,& visualize data in many ways that reveal relationships, patterns,& trends in the  form of maps, globes,reports,& charts

A GIS helps you answer questions & solve problems by looking at your data in a way that is quickly understood & easily shared & can be integrated into any enterprise information system framework

A GIS can be viewed in three ways:

1.The Database View: A GIS is a unique kind of database of the world -a geographic database (geodatabase).It is an "informationsystem for Geography."Fundamentally,a GIS is based on a structured database that describes the world in geographic terms

2.The Map View: A GIS is a set of intelligent maps & other views that show features & feature relationships on the earth's surface.Maps of the underlying geographic information can be constructsd & used as "windows into the database"to support queries ,analysis,& editing of the information.

3.The Model View: science of futureA GIS is a set of information tools that derive new geographic datasets from existing datasets.These geoprocessingfunctions take infomation from existing datasets.apply analytic functions,& write results into new derived datasets.

By combining & applying some analtic rules, you can create a model that helps answer the question you have posed.In the example below,GPS&GIS were used to accurately model the expected location & distribution of debris for the Space Shuttle Columbia , which broke up upon re-entry over eastern texas on february 1,2003.