Abstract: A navigational aid comprises a housing with a flat, transparent liquid crystal display. The display is flat and flush with the bottom of the housing, to allow the aid to be placed flat on a map or chart. The aid is microprocessor controlled and accepts plug in memory modules, which contain information relating to an area through which a craft, for example, an aircraft, is to be navigated. The display generates cursors which can be superimposed on the map. The aid can display graphically the progress of the craft, superimposed on the map, on the basis of input data supplied by the user. Alternatively, the cursors can be moved to measure the distance beteen points on the map.