Navigation apparatus and method, and computer program product

摘要

A navigation apparatus is provided with: a first storing device for storing original data for a navigation based on a predetermined format and including map data, in such a manner that an empty area exists on the predetermined format in each processing unit for a predetermined kind of navigation processing; a second storing device for storing difference update data representing a data portion for the navigation that is updated with respect to the original data as a standard; and a re-writing device for generating updated data based on the format and including the original data and merge data, by re-writing the merge data at least partially into the empty area corresponding to the merge data. The merge data defines a relationship of the difference update data with respect to the original data. The navigation apparatus is also provided with a processing device performing the navigation processing on the basis of the original data and the difference update data.