Abstract: A taxi sign device, which can display various details is provided; the taxi sign device utilizes the unit which is installed today on the taxi's roof (the yellow hat with the writing “TAXI”) and comprises a keypad or buttons for entering the driver's commands, a control unit controlling the display on the taxi's roof according to commands entered a fixed display which is not changeable for identification, an internal display which allow the driver to see status reports or to see an image of what is shown in the display on the roof; it is possible to also display distress signs and calling for help initiated by the driver.