GIS, first coined as Geographic Information Systems, is an information system for creating, storing, editing, and analyzing data related to locations on or near the Earth's surface. It provides a discipline independent environment that supports not only explicit spatial thinking and reasoning, but also interdisciplinary collaborations.
The unique character of GIS lies in storing locations explicitly as coordinates (as apposed to addresses and place names). By doing so GIS provides capabilities that are not possible in traditional data analysis environments:
GIS can easily integrate data of different types and disciplines by common geography. This can be a long, labor-intensive and error-prone, or impossible process with traditional data analysis packages.
GIS displays data in a form of maps which often reveals patterns and relationships not apparent in tables and charts. A famous example is the cholera map created by Dr. John Snow during the 1854 cholera outbreak in London. The map revealed a strong relationship between cholera deaths and a particular water pump.
- GIS allows users to explore and analyze data in numeric space and geographic space. The spatial distributions of data are important to many problems we are facing, from locating a new hospital to the impacts of climate change. Traditional data analysis packages only provide capabilities in exploring and analyzing data in the numeric space.