ArcMap is run using primarily Shape Files and in more recent versions Geodatabases can be used to store larger sets of data. These file formats are what are uploaded into the program to view spatial data.
Edema is swelling of both legs from a buildup of extra fluid. Prolonged standing or sitting, especially in hot weather, can cause excess fluid to accumulate in the feet, ankles and lower legs. Tiny valves inside the veins of the legs can become weakened, causing a common problem called venous insufficiency.
An abnormal buildup of fluid in tissues called edema is what causes swelling in the legs. In some cases, edema that results in painful swollen legs and ankles can be caused by lymphatic dysfunction. In other cases, edema can result from long-standing venous reflux, a venous disease that causes spider veins and varicose veins and can lead to more serious conditions, such as skin discoloration or venous ulcers.