Definition of GIS:

There is no clear cut definition of GIS. Different people defined GIS according to their capability and purposes for which it is applied. Some of the definition are-

1. “A powerful set of tools for collecting, storing, retrieving at will transforming and displaying spatial data from the real world” (Burrough, 1987).
2. “A computer assisted system for capture, storage, retrieval, analysis and display of spatial data, within a particular organization” (Clark, 1986).
3. “A decision support system involving the integration of spatial referenced data in a problem solving environment” (Cowen, 1988).
4. “An information technology which stores, analyzes and display both spatial and non-spatial data” (Parker, 1988).
5. “A geographic information system (GIS) is a computer-based tool for mapping and analysing things that exist and events that happen on earth. GIS technology integrates common database operations such as query and statistical analysis with the unique visualization and geographic analysis benefits offered by maps” (ESRI definition). Or a framework to organize, communicate, and understand the science of our world.
6. “A GIS is a computer system capable of assembling, storing, manipulating, and displaying geographically referenced information, i.e. data identified according to their location. Practitioners also regard the total GIS as including operating personnel and the data that go into the system” (United States Geological Survey definition).
7. “GIS is an integrated system of computer hardware, software, and trained personnel linking topographic, demographic, utility, facility, image and other resource data that is geographically referenced. If you’ve ever used an Internet mapping program to find directions, congratulations, you’ve personally used GIS. The new supermarket chain on the corner was probably located using GIS to determine the most effective place to meet customer demand” (NASA GIS definition).

There are probably as many definitions of GIS as there are authors on GIS but there are certain fundamental components that remain the same throughout:

• Geographic locations also called geographically referenced or spatial data.
• Information about the locations also called Attributes or Non-spatial data.
• Software for storing and processing the data.
• Hardware to facilitate the storage, processing and distribution of data.
• The people who operate the systems.