Overview

What is a GIS?

A geographic information system (GIS) is a computer-based tool for mapping and analyzing things that exist and happen on the surface of the Earth. GIS technology integrates common database operations such as query and statistical analysis with the unique visualization offered by maps. These abilities distinguish GIS from other information systems and make it valuable for explaining events, predicting outcomes, and planning strategies. Mapmaking and geographic analysis are not new but a GIS performs these tasks better and faster than conventional manual methods. Before GIS technology, only a few people had the skills necessary to use geographic information to help with decision making and problem solving.

What makes up a GIS?

A working GIS integrates five key components: hardware, software, data, people, and methods. Hardware is the computer on which a GIS operates. GIS software provides the functions and tools needed to store, analyze, and display geographic information. Geographic data (layers) and related tabular data are necessary in order to perform work in a GIS software. GIS technology is of limited value without the people who manage the system and develop plans for applying it to real-world problems. Lastly, a successful GIS operates according to well-designed plans and business methods, which are the models and operating practices unique to each organization.

What is a GIS layer?

A GIS stores information about the world as a collection of layers that can be linked together by geography. This simple but extremely powerful and versatile concept has proven invaluable for solving many real-world problems such as the tracking of delivery vehicles, recording details of planning applications, as well as modeling global atmospheric circulation.

Where is GIS heading?

Today, GIS is a multi billion dollar industry employing hundreds of thousands of people worldwide. It wasn’t long ago that GIS applications existed only on large platforms such as mainframes and mini computers. This limited the typical GIS user to individuals who had access to such machines. This also meant that the knowledge of operating GIS software was confined to GIS experts. Recent technological improvements in personal computing, coupled with advancements in GIS software development, have resulted in GIS technology being moved to the desktop. This has greatly increased the number of individuals who use GIS technology. Today, we observe a growing number of GIS applications being made available on the Internet, many of which can be found on the web sites of local governments. The number of GIS applications on the Internet is projected to increase, allowing even more of the population access to GIS. In short, professionals in numerous fields are increasingly becoming aware of the advantages of thinking and working geographically.

In addition to changes in computer platforms, data formats have also changed and will continue to evolve. Historically, one of the limitations of GIS data has been its inability to reside alongside and within robust database applications. All that has changed with recent improvements in database architecture that allow spatial data to reside in "true" database management systems such as Informix, Oracle and SQL Server. Having GIS data in these traditional database formats provide the advantage of a secure environment, excellent database administration tools, faster queries, improved data sharing and a host of other geospatial benefits.