These are the following reasons why a GIS is needed.
- geospatial data are poorly maintained
- maps and statistics are out of date
- data and information are inaccurate
- there is no data retrieval service
- there is no data sharing
Once a GIS is implemented, the folllwing benefits are expected.
- geospatial data are better maintained in a standard format
- revision and updating are easier
- geospatial data and information are easier to search, analyze and represent
- more value added product
- geospatial data can be shared and exchanged freely
- productivity of the staff is improved and more efficient
- time and money are saved
- better decisions can be made
Table 1.1 shows the advantages of GIS and the disadvantages of conventional manual works without GIS.
Figure 1.3 shows a comparison between geospatial information management with and without GIS.