fig1 shows a preferred embodiment of the disclosed global navigation system . it can display local electronic maps according to the location of the global navigation system to guide from current location to a destination . it should be explained that the invention can be installed in a vehicle or a portable electronic device , such as a personal digital assistant ( pda ), a palm pilot , a cell phone , or a laptop computer . in addition to basic navigation functions , the system can further includes the functions of magnifying street crosses , speeding camera alarms , planning routes , schedules , networking , e - mailing , and cell phones . the invention is characterized in that the provided global navigation system includes navigation software for all places . the system can switch among different navigation software for different regions according to the location of the global navigation system , so that the user can find any place along with related information from the electronic map displayed by the local navigation system . the navigation system contains an input module 2 , a position detection module 6 , a region selecting module 8 , a plurality of navigation modules for different regions 12 a , 12 b , 12 c , a display module 14 , and a database 16 . the input module 2 is used for the user to operate , and to select the desired functions . the input module 2 can be a remote control , a touch control panel , a keyboard , a mouse , or any other human - machine interface with similar functions . therefore , by operating the input module , the user can switch among different navigation modules or maps for different regions , initialize navigation functions , select initial and destination point on the electronic map , and zoom in and out on the map . the position detection module 6 is a receiver of the global positioning system ( gps ) that receives a satellite signal 7 to locate the current position of the user , vehicle , other transportation tool , or the global navigation system itself . the relevant information is provided to the region selecting module 8 and a guiding module 20 inside the selected navigation module ( ex . 12 a , 12 b or 12 c ). the region selecting module 8 determines the information of country and region of the current position according to the information provided by the position detection module 6 to select an electronic map that covers the current position of the global navigation system . the method of selecting a corresponding navigation module is done as follows . the information provided by the position detection module 6 is compared with the data contained in a navigation module to select a compatible navigation module ( ex . 12 a , 12 b or 12 c ). for example , the data used for comparison may be the coordinate data in an electronic map . thus , the method provides a way of selecting a navigation module with an electronic map that has the right coordinates with the country and region of the current position . the navigation module 12 a , 12 b , 12 c of different regions can be provided and installed by different companies or a single company . for example , the first navigation module 12 a , the second navigation module 12 b , and the third navigation module 12 a may have functions navigating in the u . s . a ., taiwan , and japan . each of the navigation modules includes a path selecting module 18 and a guiding module 20 . the path selecting module 18 can extract required information from the database 16 according to the information provided by the region selecting module 8 or the position detection module 6 to select the electronic map with an appropriate range according to the information provided by the region selecting module 8 . for example , it can select the electronic map of california in the u . s . a . or taipei city in taiwan . an image is then generated and sent to a display module 14 for display . relevant information can be provided to the guiding module 20 too . on the other hand , the path selecting module 18 can determine an initial point and a destination point according to the navigation instruction given from the input module 2 by the user and find a guiding path connecting the initial and destination point . after the guiding module 20 receives the information of the guiding path , the current position , and the electronic map , it can generate a resulting image and sends it to the display module 14 for display . the display module 14 in this embodiment refers in particular to a liquid crystal display ( lcd ) for displaying images . of course , other displays such as the cathode ray tube ( crt ) and the plasma display can achieve the same function too . the database 16 is a storage medium such as an optical storage medium ( cd , dvd ), a hard disk drive ( hdd ), a memory card , or other equivalent devices . it stores the data of electronic maps for different countries and regions . the data include terrain characters in a region , such as the roads , street names , crosses , attributes , two - dimensional ( 2d ) coordinates , and other traffic related information . it should be noted that the database 16 here contains electronic maps of multiple regions and multiple countries . it covers at least the electronic maps of major countries in the world , such as the america , japan , china , australia , britain , france , italy , germany , new zealand , russia , and swiss . although we only depict one database 16 in the current embodiment , the electronic map data of different regions can be stored together or separately at various storage positions in practice . that is , the scope of the invention is not restricted by the example shown in this embodiment , but defined by the claims . this embodiment uses only three navigation modules for the purposes of illustration . the actual number of navigation modules for different countries and regions in the world can be adjusted by the user or manufacturer according to needs . in summary , the disclosed system can switch to an appropriate local electronic map to provide the required navigation functions according to the location of the global navigation system . the user is thus prevented from getting lost when traveling among countries . we use a preferred embodiment and the accompanying drawing to explain the disclosed method . as shown in fig2 , the navigation system locates the user , the vehicle or other transportation tool installed with the disclosed system , or the global navigation system itself ( by identifying the country or region , for example ) according to the satellite signal 7 received by the position detection module 6 ( step 201 ). the region selecting module 8 takes the information provided by the position detection module 6 ( e . g . the current position of the user or system ) and compares it with data contained in each of the navigation modules , thereby finding a compatible navigation module ( ex . 12 a , 12 b or 12 c ) and initializing its functions ( step 202 ). the function initialization can be as simple as displaying an electronic map covering an appropriate range around the current position ( step 203 ). once a navigation command is received , the system can provide the necessary navigation functions for a particular location . in summary , the invention indeed can enable the user to use local electronic maps to find out his or her current position and therefore to make use of the navigation function , wherever the country or region is . that is , when a user is traveling among different countries , he or she will not get lost by switching the system to the local map and navigation function according to the invention . consequently , the invention is able to solve the problem of the current design of localized navigation systems that are restricted to fixed regions . certain variations would be apparent to those skilled in the art , which variations are considered within the spirit and scope of the claimed invention .