Patent ID: 8078393

Claim:
A navigation apparatus comprising: a map information storage unit that stores map information; a storage medium driving unit in which a storage medium for storing map update information used for updating said map information is mounted; a map information updating unit that updates the map information stored in said map information storage unit on a basis of the map update information read from the storage medium mounted to said storage medium driving unit; a mounting detecting unit that detects whether or not the storage medium is mounted to said storage medium driving unit; a map information ID comparison unit that compares a map information ID attached to the map information stored in said map information storage unit with a map information ID attached to the map update information stored in the storage medium mounted to said storage medium driving unit, and judging whether said compared map information IDs match each other; a map information selection control unit that selects a part of the map information stored in said map information storage unit under conditions where the mounting detecting unit detects the storage medium being mounted to the mounting detecting unit and the map information ID comparison unit judges that said compared map information IDs do not match each other; a navigation information calculating unit that creates navigation information by carrying out an predetermined operation on a basis of the map information selected by said map information selection control unit; and a navigation information output unit that outputs the navigation information created by said navigation information calculating unit.