An area of interest (AOI) is defined by a polygon feature that represents a specific geographic extent. In ArcGIS Defense Mapping, AOI features are found in an index feature class that contains various map extents for a region or the world. The index feature class resembles a grid on a map; each cell in the grid is an AOI polygon feature that can be selected. The size of each cell depends on the type of map product and the AOI index you are working with. Some map products have different scales, which require different AOI sizes.
Map Production System web app AOIs
The self-serve Map Production System (MPS) web app uses AOIs to define the extent of a map product export. It uses the AOI index feature class on a web map that is prepared and shared from ArcGIS Pro. Each AOI feature becomes a potential map extent for the map products that the app can export.