What is Geographic Information System (GIS)?
(Taken from ESRI, 2010. www.gis.com)
A GIS allows us to view, understand, question, interpret, and visualize data in many ways that reveal relationships, patterns, and trends in the form of maps, globes, reports, and charts. GIS can provide many important things:
Map Where Things Are - GIS allows the user to look at the distribution of features, not individual features, to see patterns.
Map Quantities - Mapping quantities allows the user to find places that meet their criteria and take action, or to see relationships between places.
Map Densities - This is useful when mapping concentrations of features using a uniform areal unit, such as acres or square miles. This allows you to see distribution of features very clearly.
Find What's Inside - GIS allows you to monitor what's happening in specific areas and to take action. For example, Emergency Response can map hazardous spills to determine who to evacuate within a 10-mile radius from the accident.
Find What's Nearby - Features can be mapped to determine what is occurring within a certain distance. An example is to map a floodplain feature on top of aerial photography to determine where the flooding threatens public and private structures.
Map Change - Mapping change in an area can provide insight into future conditions by allowing users to see where and how things move over a period of time.