The past four decades have seen quite a revolution in the way people view their neighborhoods, towns and cities: a revolution brought about by the computer technology known as GIS, or Geographic Information Systems. GIS was developed to solve real world problems. It is now commonplace for businesses, government and academia to use GIS for many diverse applications. Consequently, many definitions of GIS have developed. The most commonly used one today describes it as 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 data. With GIS, people are using computers to analyze all types of issues with their geographic data, and in doing so decisions are better informed than has ever been possible before -- the age of the digital map is here.
The key to an effective GIS is an accurate and up-to-date base framework with an organizational structure that promotes enterprise-wide use and prevents duplication of effort. GIS offers real promise in being able to assist individual County departments in achieving their respective objectives. Furthermore, the geographic and spatial nature of GIS has been shown to facilitate inter-departmental relationships. This can help to promote a more comprehensive and holistic approach to government and public service.
Today computers are cheaper and faster than ever, GIS software is easier to use, and geographic data is more readably available. Whether you work in the private or public sector you can apply GIS to save time and money in your work. Many computer programs such as spreadsheets (i.e. Microsoft Excel), statistics packages (i.e. SAS), or drafting packages (i.e. AutoCAD) can handle simple geographic or spatial data. Why, then, are they not usually thought of as a GIS? The generally accepted answer is that a GIS is only a GIS if it permits spatial operations on the data (i.e. analysis of areas, linear features and point information in relation to each other).
Although GIS provides a great means for power-mapping, it is not simply a computer system for making maps, even though it can create maps at different scales, in different projections, and with different colors, GIS is an analytical tool. The major advantage of a GIS is that it allows you to identify the spatial relationships between map features. A GIS does not store a map in any conventional sense; nor does it store a particular image or view of a geographic area. Instead, a GIS stores data from which you can draw a desired view to suit a particular purpose.
A GIS links spatial data (i.e. graphical map elements) with geographic information (i.e. databases, spreadsheets, CAD drawings, pictures) about a particular feature on the map. This information is stored as attributes of the graphically represented features. A GIS also uses stored features to compute new information about map features (i.e. to calculate the length of a particular road segment or to determiner the total area of a particular soil type represented on a map). GIS has the built-in capability to perform these type of operations.
In short, a GIS doesn't hold maps or pictures -- it holds a database. The database concept is central to a GIS and is the main difference between a GIS and drafting and computer mapping systems, which can only produce good graphic output. A GIS incorporates some type of database management system. Since a vast amount of data is stored in some form of database and normally has a geographic link, the application of GIS is limited only by the imagination of those who use it. GIS is revolutionizing how we work and how we solve problems. That is what makes GIS so exciting.