Navigation device and method for marking traffic conditions on navigation map

A navigation device comprising:

• a data storage for storing a navigation map, a keyword database storing a plurality of keywords, wherein the plurality of keywords are grouped into road keywords and traffic condition keywords, each road keyword being mapped to a road on the navigation map, and each traffic condition keyword corresponding to a traffic condition and being designated a traffic condition mark;
• a display for displaying the navigation map;
• an audio receiving unit for receiving audio forwarded by a radio device;
• and
• a processing unit comprising:
• an audio analyzing module for receiving the audio forwarded by the radio device, and seeking to obtain road keyword and traffic condition keyword associated with the road keyword in the audio after the audio has been converted to a digital signal;
• a traffic condition marking module for determining the corresponding road on the navigation map of the detected road keyword and determining designated traffic condition mark of the associated traffic condition keyword of the road keyword, and marking the determined road on the navigation map with the determined traffic condition mark.