A Geographic Information System, or GIS, integrates, data, hardware, software and GPS to assist in the analysis and display of geographically referenced information.
GIS is a general term that refers to any scientific effort integrate data to help researchers visualize, analyze, and explore geographically referenced information. For example, GIS is helping researchers measure the speed of glacier melting in Greenland and Antarctica. GIS can assist in the analysis of small-scale and localized data, as well, such as development trends, or watershed analysis.
The field of GIS has advanced rapidly in recent years, with the availability of rapidly increasing computer power, development of software, and proliferation of inexpensive GPS devices.
GIS is frequently used to create maps that illustrate hidden data. For examples, visit Geodata.gov.