What is GIS?

Information referring to places and events relative to their location on the earth's surface is often defined as geographic or spatial data. Geographic Information Systems (GIS) are computer systems designed to create, store, retrieve, analyze, and display geographic data. Fundamental to the design of GIS is the integration of geographic data with information about the geographic feature. Many types of information about our community are stored in distinct map layers. These layers contain point, line and polygon map features. A fire hydrant or a permit location may be stored as a point. Roads, water mains, and rivers are stored as lines. Parcels, school districts, and zip codes are stored as polygons.



The image above demonstrates the linking of geographic, tabular and image data. This data provides information about objects found on the earth's surface including their locations, shapes and descriptions.

Beginning in the 1960's, experts from a variety of disciplines began to experiment with the use of computer systems for storing and manipulating geographic information. From the start, these professionals were driven by a need for tools and procedures to solve the practical problems of explaining events, predicting outcomes and planning strategies based on geographic location. This practical orientation continues to drive what has become a multi-million dollar industry, with applications ranging from retail site location to environmental impact analysis.

The five major components of a GIS are data, software, hardware, people and procedures. By putting these pieces together, public agencies and private companies are finding that the use of GIS technologies translates into substantial benefits by empowering people to make better decisions, integrate information from many data sources, visualize data, provide for efficient data management, and improve customer service.