GIS (Geographic Information Systems) is computerized cartography, which is used to create, edit, store and retrieve, update, manipulate and display geographically referenced digital data. Through the use of a GIS, common mapping features such as roadways and water mains can be linked with associated tabular attributes and viewed graphically on a map. Rather than seeing just a few key features on a static map, GIS mapping allows you to view customizable combinations of data layers in a dynamic tool.
GIS mapping helps visualize and identify patterns that are difficult to see if the data elements are in table format. It also helps to identify patterns that emerge when you view two or more datasets together.