Geographic Information System definition application
(GIS) A computer system for capturing, storing, checking, integrating, manipulating, analysing and displaying data related to positions on the Earth's surface. Typically, a GIS is used for handling maps of one kind or another. These might be represented as several different layers where each layer holds data about a particular kind of feature (e.g. roads). Each feature is linked to a position on the graphical image of a map.
Layers of data are organised to be studied and to perform statistical analysis (i.e. a layer of customer locations could include fields for Name, Address, Contact, Number, Area). Uses are primarily government related, town planning, local authority and public utility management, environmental, resource management, engineering, business, marketing, and distribution.
GIS dictionary (http://geo.ed.ac.uk/root/agidict/html/welcome.html).