Map information distribution systems and methods store map information and version information for each road category of the map information stored in a navigation device, the version information correlated with identification information identifying the navigation device. The systems and methods receive the identification information from the navigation device and obtain, based on the received identification information, the version information for each road category of the map information stored in the navigation device corresponding to the stored identification information. The systems and methods extract, based on the obtained version information for each road category, differential data for each road category with stored map information of a latest version, and transmit the extracted differential data for each road category to the navigation device corresponding to the received identification information.