There are two types of maps:
Raster map is a simple electronic reproduction of the corresponding paper map. It is not "smart" nor navigable can only be printed or displayed as a paper map.
Vector map (or navigable): is a structured database that contains various types of data, including the geometry of roads (ie their fitness), the attributes of the roads (name, direction of traffic, turning restrictions, and so on) , the names of the cities, points of interest (POI), the codicipostali, house numbers and so on.
The TomTom navigation devices use vector maps, with a raster map overlaid at some zoom levels to improve the final visual result.
Want to see Cairo with map of USA? hm ... to search long and hard.
Who thinks he can see a map as Egypt in a file type immagine JPEG (.jpg) 392 KB?
Good luck in search Cairo with this map Tom Tom USA