GIS (Geographic Information Systems) is a combination of hardware, software, and data that allows users to analyze information based on its geography. Typically, a GIS is represented as several different layers where each layer holds data about a particular kind of feature. Each feature is linked to a position on a map and a record in an attribute table.
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 soil 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.