Geographic information system (GIS) is a computerized system for storing, organizing, and analyzing geographical information. A GIS may store information on climate, geology, landforms, population, transportation, wildlife, and other data. A GIS includes the computers to store and analyze the information and the software (computer programs) necessary to operate them. A GIS often displays information in the form of maps, but it also shows tables, charts, and graphs.
Each piece of information in a GIS is connected to a specific geographical location or area. Data on rainfall, for example, may be organized by latitude and longitude, while information on population may be arranged by postal codes, such as ZIP Codes. GIS users can relate many different kinds of information about the same geographical area. An engineer, for example, can use a GIS to find a suitable location for a toxic waste disposal site. The GIS could relate information on geology, transportation, population, and water to help the engineer find a site on solid ground that is near transportation but safely away from homes and water supplies.
Many people who work with geographical information use GIS’s. Mapmakers use them to create extremely accurate maps. Engineers and planners use GIS’s to find suitable sites for power plants, roads, and other structures. A GIS can help resource managers track environmental changes, such as deforestation (the clearing of trees) and pollution. Government officials can establish and analyze emergency response plans using a GIS. Other GIS users include farmers, marketers, military officials, and scientists.
See also Map (Production and reproduction) .