The below mentioned article provides a short notes on Geographic Information System (GIS).
GIS or geographic information system combines layers of information about a place or area to give a better understanding of it. For a full GIS, one requires hardware (computers and peripherals), software, data and sound analysis methods for interpreting the results generated by the GIS.
GIS may be used for the following:
(i) Mapping where things are, which allows one to find places that have the features one is looking for and to see where to take action.
Mapping where things are lets one:
a. Find a feature — One uses maps to see where or what an individual feature is.
b. Finding patterns — By looking at the distribution of features on the map instead of just an individual feature, one can see patterns emerge.
(ii) Mapping quantities:
One map quantities to find out the dominance of a feature of interest in a particular area i.e., where the most and least are, which allows one to find places that meet the required criteria and take action, or to see the relationships between places. Instead of simply mapping the locations of features, mapping quantities give an additional level of information.
(iii) Mapping densities:
While one can see concentrations by simply mapping the locations of features, it may be difficult to see which areas have a higher concentration than others in areas with many features. Density map lets one measure the number of features using an uniform aerial unit, such as acres or square miles, so that one can clearly see the distribution.
(iv) Finding what’s inside:
GIS can be used to monitor what is happening and to take specific action by mapping what is inside a specific area.
(v) Finding what’s nearby:
GIS can be used to find out what is occurring within a set distance of a feature by mapping what is nearby.
(vi) Mapping changes:
Future conditions can be anticipated by mapping the change in an area, which allows to decide on a course of action, or to evaluate the results of an action.
For GIS analysis, one must proceed in the following way:
(i) Frame the question:
GIS analysis should be started by figuring out what information one needs.
(ii) Selection of data:
The type of data and features one works with helps determine the method one uses.
(iii) Selection of an analysis method:
One must decide on which analysis method to use based on the original question and how the results of the analysis will be used.
(iv) Processing of data:
Once the analysis method has been selected, one will need to process the data in a way that makes sense for one’s goal.
(v) Looking at the results:
The final step is to look at the results of one’s analysis and take action based on those results. The results can be displayed as a digital map, printed as a paper map, combined with spread sheet-like tables or charts, or displayed as such. Though in GIS, a lot of emphasis is given on making maps, the software is flexible enough to allow one to display the results in the format that best suites ones needs.
Thus, the benefits of GIS lie in the fact that it allows:
(i) Improved organizational integration i.e., improved management of one’s organization and resources.
(ii) Make better decisions i.e., better information leads to better decisions. A GIS is not just an automated decision making system but a tool to query, analyse, and map data in support of the decision making process.
(iii) Make maps i.e., GIS creates maps from data pulled from databases and GIS is flexible enough to map any kind of terrain, even the human body.