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.
Swollen legs can be caused by lymphodema. In addition to arteries which supply the leg with blood and veins that take the blood from the leg, a lymphatic system clears materials which escape from the circulation. If your lymphatic system is poorly developed or becomes blocked, you are at risk of developing swelling.