Geographic Information Systems (GIS) is a computer-based tool used in a variety of industries to map and analyze where things exist and events happen on earth. GIS technology integrates common database operations such as query and statistical analysis with the unique visualization and geographic analysis benefits offered by maps. These abilities distinguish GIS from other information systems and make it valuable for use in a wide range of applications for explaining events, predicting outcomes, and planning strategies.

GIS is a valuable tool for performing information analysis, automated mapping and data integration. There are many components necessary to make a GIS function properly, including an organized collection of computer hardware, software, geographic data, and personnel designed to efficiently capture, store, update, manipulate, analyze, and display all forms of geographically referenced information. The common denominator in GIS is geography, or spatial distribution and location (e.g., coordinates of an irrigation well, an address of a house). Geographic information also includes information about those features such as the capacity of the irrigation well and the value of the house. It is precisely this ability to link spatial location with descriptive or attribute data that makes a GIS so powerful.

Essentially, any set of data that has a spatial extent and is referenced with a geographic identifier- such as an address, parcel ID, or latitude/longitude- can be utilized in a GIS to answer questions and solve problems. A GIS typically addresses questions and problems related to location proximity, conditions, trends and patterns.

Additionally, a GIS can be used to perform analytical operations to support decision-making processes, such as site suitability analyses for future landfills or soil erosion potential within a specific region. A GIS can also answer "what if...?" questions based on different scenarios and situations. A GIS can be used to automate existing operations (e.g., map production and maintenance), as well as provide enhanced capability to analyze geographic information for decision-making purposes.

One of the most powerful features of a GIS is its ability to simultaneously use multiple discrete spatial data sets to answer questions that were previously impossible to answer using conventional mapping methods. By inputting spatial information into a GIS, we can query data based on its location in the real world.When we link our spatially referenced data to an existing database and query based on a geographic identifier and attribute, we add another dimension to our query, giving us results impossible to acheive from a database alone.

When used as a result of proper planning and attention to detail, a GIS allows the end user to make better decisions quicker, and provides planners, engineers and technicians with the ability to make sense out of data that may otherwise be overlooked. A GIS combines the best of map making with the best of database management, resulting in a powerful combination of visual and computational analysis.