A method for operating a navigational system, especially a navigational system for a motor vehicle, having a memory, a display unit and at least one operating element, map data being loaded from a map data memory into the memory; the map data being subdivided into first map data and second map data; the first map data including geometric data of edges of a map network stored as graphs, and the second map data including topological data and applications being carried out using the first and/or second map data loaded into the memory.