A Geographic Information System (GIS) is a technology that is used to view and analyze data from a geographic perspective. The technology is a piece of an organization's overall information system framework.
GIS links location to information (such as people to addresses, buildings to parcels, or streets within a network) and layers that information to give you a better understanding of how it all relates with each other.
Hidden in most data is a geographical component: an address, postal code, census block, city, county, or latitude/longitude coordinate. With GIS, you can explore the spatial element of your data to display many types, track crime patterns, analyze animal migration patterns, find the best location for an expanding business, model the path of atmospheric pollution, and make decisions for many types of complicated problems.