1. A navigation device adapted to be installed on a vehicle and enabling information to be provided to an occupant of the vehicle, the navigation device comprising: a display section displaying an image to an occupant of a vehicle; a speech recognition section executing speech recognition processing for a voice input relating to a speech recognition object word that is a word to be an object for speech recognition, in such a manner that in a case that a failure occurs in recognition as to the speech recognition object word, second speech recognition processing is executed for the speech recognition object word except for the speech recognition object word present in the image currently displayed in the display section; and an information providing processor section compelling a predetermined image to be displayed on the display section based on a recognized content resulting through the speech recognition processing in a case that the speech recognition object word is recognized through the speech recognition processing.