Patent ID: 7526492

Claim:
A method of displaying map data of a road system on a display device, the method comprising: obtaining node data which indicates information concerning nodes that represent points along a road; obtaining link data which indicates information that identifies a link that represents a road between the points; forming a link row which represents a series of roads as a series of links in the road system; forming link row data in which the link data for links constituting the link row are arranged in the order that the links are connected; assigning node identifiers which identify the nodes; expressing the road system by using the nodes and the links; and displaying the road system on the display device, wherein, the node data for each of the nodes of the road system are provided separately from the link row data; wherein, the node identifiers are provided for each of the nodes of the road system; and wherein, the link data includes information that indicates the node identifier for only one node located at one link end that is defined in accordance with the direction of the link row.