in the following , the present invention will be described using different exemplary embodiments . since in the present invention route recommendations are given as a function of risks , some more detailed considerations regarding different risk types are to be made first ( see also fig4 ). in one exemplary embodiment of the present invention , risks are divided into static and dynamic risks , it being possible to further subdivide dynamic risks into weak - dynamic and high - dynamic . static risks may occur permanently , may occur as a result of a time - variation curve , and / or may occur as a result of season . a permanent risk may be assumed for specific urban areas ( for example , the bronx , n . y .) or for specific routes . a static permanent risk of a route may be assumed , for example , if the route is confusing , passes through a tunnel or an underpass , is steep , deserted , or slippery . for this purpose , in one additional exemplary embodiment it is provided that a user may evaluate or weight the individual risks in his system control , ideally in advance . this may lead to an older person completely avoiding steep routes , for example , while a younger person sets the risk to only 10 %. analogously , evaluations for underpasses may have differing strengths for women and men . at the same time , while individual conditions present a risk for all users equally ( possibly having different weights ), for example , an urban area such as the bronx , n . y . would present a certain risk for pedestrians , cyclists , inline skaters , and also motorcycle and car drivers at all times ; likewise , specific conditions of the route , such as grade crossings , also present a risk for all users at all times and should thus be categorized as a permanent risk . other permanent risks are relevant only for individual users , such as motorists or pedestrians / cyclists . for example , routes having numerous turning maneuvers or lane changes for vehicles 03 could be evaluated as having an increased risk . in contrast , routes having existing bike paths would be preferable for cyclists , that is , should be evaluated as having a lower risk than routes without bike paths . for cyclists and pedestrians , for example , the evaluation of route conditions such as confusing , steep , deserted , or slippery routes would be valuable , whether the route has underpasses , or whether many crossings without traffic lights are necessary or wide roads without crosswalks have to be crossed in a route . specific regions or specific routes , for example , city centers or arterial roads , during rush hour , or roads , parks , and places at night , should be evaluated as having a varyingly high risk resulting from a time - variation curve . here too , as a rule the estimation of the risk for vehicles 03 would have to be evaluated differently than that for pedestrians or cyclists . for vehicles 03 , areas or routes should be evaluated as having a higher risk during rush hour , while the criterion “ street , park , or place at night ” is significant for pedestrians and cyclists . for example , passes in winter are static , seasonally driven risks for all road users . additionally , static seasonally driven and time - variation - curve - driven risks may be taken into account in the route calculation ; this includes , for example , deer crossings during mating season at twilight , which are taken into account in particular for the route calculation for vehicles 03 in one exemplary embodiment of the present invention . in another exemplary embodiment of the present invention , static quasi - permanent risks are taken into account in the route calculation or route evaluation as a further subgroup of the static risks . this includes , for example , construction sites with corresponding lane constrictions , which are to be categorized as a risk for all road users . in one further exemplary embodiment of the present invention , a “ weak - dynamic ” risk group is provided . the weather would be one such weak - dynamic risk , which is included , and possibly weighted differently , in the route calculation for all road users so that during a thaw paths having many curves , poor paving , a high altitude above sea level , gravel roads , or the like are evaluated as having a correspondingly higher risk in the corresponding weather conditions . other weak - dynamic risks are , for example , specific driving behavior , short - term construction sites , or demonstrations , rallies , or sporting events , which are accordingly weighted , for example , with regard to a danger when turning left , when changing lanes , when driving in the city or in snow ( specific driving behavior ), in the event of lane constrictions ( short - term construction site ), or in the presence of hooligans ( demonstrations , rallies , or sporting events ). a further important risk group for the evaluation of the routes is high - dynamic risks , which result in particular from the current driving situation of vehicles 03 . in this context , information regarding the surroundings of vehicle 03 , the velocity of vehicle 03 , and / or possible alternative routes are taken into account . in this context , the information regarding the surroundings of vehicle 03 is ascertained by sensor systems such as radar sensors , video sensors , car2car sensors , car2infrastructure sensors , or the like . these parameters are then taken into account in the evaluation of driving maneuvers for the provided travel route , such as necessary lane change or turning maneuvers . in one exemplary embodiment of the present invention , static and possibly weak - dynamic influences are taken into account already in the preliminary stages in the route calculation ; high - dynamic influences are included in the calculation at short notice . driving recommendations may be output in various ways as a function of the risk type : for example , in the event of static risks , instructions for the optimal route could be given early in order to avoid distracting the driver with instructions in high - risk situations ; in the event of high - dynamic influences , suboptimal instructions could be given in high - risk situations in order to avoid risky driving maneuvers . in low - risk situations , it could be provided that a plurality of alternative instructions are given , the sequence of the alternative instructions and / or supplementary information for the alternative instructions indicating to the user of the navigation system the advantages and disadvantages associated with the respective routes . because the pedestrian has time to concern himself with the route guidance , another exemplary embodiment provides outputting additional information about which risks lie on which routes , so that the user himself may decide which way is the most favorable for him . in one possible embodiment , the present invention may be executed as an upgrade to a traditional vehicle navigation system 01 . in such an exemplary embodiment , vehicle navigation system 01 has a connection to external sensors 02 , such as radar sensors , video sensors , car2car sensors , and / or car2infrastructure sensors , for example , via a bus system or an air interface . these sensors 02 provide information about the current traffic situation in the surroundings of vehicle 03 . with the help of this information , vehicle navigation system 01 may evaluate the risk of performing a driving maneuver that is optimal in terms of time and distance , that is , a maneuver that follows the shortest , quickest , or optimal route . to this end , in one exemplary embodiment , navigation system 01 includes means 04 for evaluating the risk in following the optimal driving instruction and means 05 for determining driving instructions that are optimal in terms of safety , taking into account a possible detour . in one exemplary embodiment , means 05 for determining driving instructions that are optimal in terms of safety weights the risk relative to a possible detour or time loss . if this risk is small , for example , straight - ahead driving or turning on a one - lane road , the optimal driving instruction is output . however , if the risk is relatively high , for example , when turning on a street having multiple driving lanes 06 , whereby lane - changes would be necessary in dense traffic , under certain circumstances the suboptimal driving instruction is output . fig2 shows such a situation . currently , vehicle 03 is located in the outermost left lane . according to the optimal travel route , the driver would actually have to turn right and to this end would have to change lanes twice in dense traffic , however . for this reason , here a “ straight ” would be recommended , as long as the resulting detour is not too long . the optimal driving instruction is given earlier than usual so that the driver has more time to situate himself correctly and to execute the driving maneuver safely and in a stress - free manner . one possible development stage of this system provides informing the driver explicitly that following this optimal driving instruction is important since otherwise a detour of x km would automatically result along with the corresponding time loss , for example , because no other expressway exit exists within the next 20 km . a suboptimal driving instruction is given , for example , a recommendation is made to the driver to continue driving straight , but to keep right , even though he actually should have exited the expressway . the detour resulting thereby should , however , have a reasonable relationship to the risk that following the optimal driving instruction would have meant . in this case , the driver possibly does not even notice that he actually should have left the expressway and arrives at the destination in a manner that is more stress - free , since he does not attempt to follow the driving instruction at all costs . at the next exit , he is then prompted to exit . a plurality of alternative driving instructions is given , for example , a recommendation is given to the driver to drive straight or to turn right . in this context , the sequence of the instructions could make it possible to distinguish between optimal and suboptimal instruction . in an additional development stage , distances and / or times for the alternatives could possibly be output as well . a further variant provides — in particular when a car2car sensor is present — that host vehicle 03 coordinates its intention to turn with other road users 07 , in order to be able to then cooperatively and uncritically travel the optimal path . in an alternative embodiment , it is provided that a route is calculated for all possible exit paths of an intersection and the driver is provided with time and distance information for these alternatives . in order to clearly inform the driver about the alternative travel routes , vehicle navigation system 01 is equipped with means 08 for outputting driving instructions that are optimal in terms of safety , for example , a human - machine interface ( hmi ). advantageously , means 08 for outputting driving instructions that are optimal in terms of safety are provided with possibilities for the acoustic and also visual output of the driving instructions . for the optical output , a color identification of the different paths may be provided ( see fig3 ) ( dark paths are to be preferred , for example , light ones are worse , depending on the gray - scale value , the driver then sees at a glance which possibilities are really worth discussing ). alternatively , one could also work with colors , thickness of dashes , solid or dotted display , etc . acoustically , one could analogously work with volume or sequence of the instruction . however , the previously described turn - by - turn displays may be transferred analogously to 2d or 3d displays , that is , it is possible to use a display in any scale of the 2 or 3 dimensional map . in certain situations , this has the advantage that the driver obtains a larger overview of the varied highway routing . ( for example , 3d displays of the pictograms with the route , or in the video image / photo .) in addition to corresponding sensor system 02 , knowing , for example , the number of lanes 06 and the turning possibilities on individual lanes 06 is important in all of these scenarios , which means that when the method according to the present invention is executed , relevant map material is accessed . the points listed above for vehicle navigation systems 01 are also essentially valid for navigation systems that are used by pedestrians , cyclists , inline skaters , other recreational athletes or other users who move at a lower speed . such navigation systems are then as a rule installed on mobile terminals , such as personal digital assistants ( pda ), for example , electronic travel guides , or mobile phones . on the other hand , in the different embodiments , it is advantageous to take into account some special risk types that occur in this group and that are described in more detail above ( see also fig4 ). the present invention is not limited in its embodiment to the preferred exemplary embodiment stated above . rather , a number of variants could conceivably make use of the system and the method according to the present invention even for basically different types of embodiments .