Which GIS operation computes the exact overlapping area between two polygon layers?

Which GIS operation computes the exact overlapping area between two polygon layers?

• A. Union
• B. Intersection
• C. Difference
• D. Symmetric Difference

Answer: (B)

Intersection is the GIS operation that computes the exact overlapping area between two polygon layers. It outputs the geometry that lies in both inputs, so you get only the region where they share space. For example, if two polygons overlap like two intersecting fields, the result is the rectangular (or polygonal) area where they coincide. This differs from union, which combines all areas from both polygons; difference, which removes the second from the first; and symmetric difference, which keeps areas that are in either layer but not in both. The intersection thus isolates the common region and often carries attributes from both inputs, making it the precise tool for finding shared areas. If there’s no overlap, the result is empty.

Intersection is the GIS operation that computes the exact overlapping area between two polygon layers. It outputs the geometry that lies in both inputs, so you get only the region where they share space. For example, if two polygons overlap like two intersecting fields, the result is the rectangular (or polygonal) area where they coincide. This differs from union, which combines all areas from both polygons; difference, which removes the second from the first; and symmetric difference, which keeps areas that are in either layer but not in both. The intersection thus isolates the common region and often carries attributes from both inputs, making it the precise tool for finding shared areas. If there’s no overlap, the result is empty.