GIS is an information technology which stores, analyses and display both spatial and non-spatial data.
1. To m aximize efficiency of decision making and planning
2. To provide efficient means for data distribution and handling
3. To eliminate redundant database-minimize duplication
4. To integrate information from many sources.
5. To generate new information via complex analysis/queries involving geographical reference data.
6. To update data quickly and cheaply.
For any application there are five generic questions a GIS can answer-
- Location: What exists at a particular location? This question seeks to find out for the answer like, location of a particular object or area in terms of latitude/longitude or X/Y.
- Condition: Identify where certain condition exists. This tends to answer for all those questions where certain conditions are satisfied.
- Trends: What has changed since? This question is applied to find a noticeable difference or change incurred within a particular time period.
- Pattern: what spatial pattern exists? This is the most logical question is answered by GIS that distribution of spatial features and reasons behind that distribution.
- Modeling: What if?