The three possibilities of GIS are explained below.

Overlay analysis: Overlay analysis is used for understanding the mutual relationship between and the changes undergone by the various features on the earth’s surface. 

For example, using maps showing the states of India and the cotton cultivated regions, we can find out the states where cotton is cultivated, using overlay analysis. This analysis also helps to find out the changes in the extent of crops and land use patterns.

Buffer analysis: In buffer analysts, a circular region is created around a point or corridor like region around a linear feature. 

For example, if the width of an existing road is increased by 10 m, we can find out the number of houses to be acquired, using buffer analysis.

Network analysis: Linear features such as roads, rivers, and railway lines are subjected to network analysis. Using this, we can find the nearest road to reach a place, less congested roads, roads without toll and hospitals, hotels and petrol pumps along the road.