You can learn more about this field by reading books about GIS technology. Most are textbooks or geared toward professionals, but browsing them can provide you with a good overview of the field. Visit the ESRI's Web site (http://www.esri.com) for books and educational tools about GIS. Finally, if possible, visit a business that uses GIS and talk to workers who use this technology. You might also ask your science teacher to arrange an information interview with a GIS specialist.

GIS is basically a computer system that can assemble, store, manipulate, and display geographically referenced information. GIS specialists use this computer technology to combine mapmaking techniques with massive databases. The data are cataloged according to location, stored in map form, and analyzed as though they were a map rather than a list. The databases might include physical geographic data, demographics, census information, or epidemiology. Environmental planning and natural resource management find GIS particularly useful, but the techniques are now being applied to a variety of disciplines, including scientific investigations, homeland defense, and crime analysis. 

Planners and developers plan a detailed scheme for a project before any work is begun to make sure objectives are met, whether they are saving a wildlife habitat, putting a transportation system in place, or guiding a booming city's expansion. Such projects require an environmental impact statement documenting the effect of the project on the environment. GIS quickly integrates lots of different types of data so that planners can spend more of their time studying the data and developing solutions.

GIS can show two- or three-dimensional maps of a region's natural features; current land and water use; distribution of housing, recreational areas, industry, and other existing development; ownership patterns; demographics of current residents; and other information. GIS then might be used to simulate growth patterns for the area and try various development plans to anticipate and prevent adverse environmental impacts.

In natural resource management, research scientists use GIS as part of efforts to build understanding about the natural resources. For example, geologists and other research scientists for the U.S. Geological Survey gather and study data relating to coastal erosion and pollution, such as along the mid-Atlantic coast, Gulf Coast, and other areas, in order to help them learn how to stop the erosion. This data includes everything from the movement of sediment during storms to wind, wave, and weather patterns. Systems that allow the scientists to pull all the data together and analyze it in different ways are indispensable in such work.

GIS technology is also used frequently by geologists (especially those who work in the natural gas and oil exploration fields). GIS technology provides geologists with the ability to digitally map and interpret the features of a geologic site in three dimensions and present this information in a variety of formats on virtual globes (also known as geobrowsers and digital globes) such as Google Earth, Bing Maps Platform, and NASA World Wind. Interactive geologic maps built within the Google Earth environment allow users to independently view individual map components (units, faults, etc.), data points, and sample locations with associated metadata (orientation measurements, small-scale structures, outcrop photos, etc.), and related components, like cross sections. Information can be inputted from site visits, existing maps, aerial photographs, on-site photographs, satellite images, and Global Positioning Satellite (GPS) data. Exact coordinates are then created on the map; this is called georeferencing. 

GIS specialists are computer experts. Digitizers are entry-level GIS workers with little experience. They convert hard copy maps to digital formats. GIS technicians have more experience with GIS software, such as ArcGIS for Desktop Basic and ArcGIS for Desktop Advanced, and do mapmaking (cartographic output) and data manipulation. They are able to do some basic computer programming. GIS analysts perform more complex analysis and relational database management, and they have more programming experience. Most GIS software is designed to allow specialists to customize it using object-oriented programming languages, such as Visual Basic. Geographic information officers are GIS specialists who manage, plan, and develop strategies relating to GIS technology at the institutional level.