A Geographic Information System (GIS) is an information system devised to work with spatial or geographical data, enabling operations such as geo-data capture, storage, analysis and display. GIS allows the precise location and display of several layers of information on a single map, for instance aerial views of the buildings, places of interest and entertainment, statistical data about neighbourhoods such as population density and pollution levels, and others. GIS mapping refers to the process by which geo-located data are charted onto maps. GIS applications are systems that display or use GIS-data. Google Maps are examples of GIS applications.
GIS technology enables the visualisation of complex data sets in relation to their location on a map, which makes it a useful tool for many disciplines and for enhancing public access to information. For example, GIS allows citizens to learn about a neighbourhood, including data regarding education, number of schools, safety and entertainment. It also allows researchers to make sense of complex data sets in relation to spatial location, and also picture their evolution in time.