KeysThe following keys are required for Series 60 UI:navigation keys Scroll upScroll downScroll leftScroll rightSelect keysoftkeys Left softkeyRight softkeycall handling Send keyEnd keyother Applications keyITU-T numeric keypad (0-9, *, #)Clear keyEdit keyPower keyThe navigation keys can be ordinary buttons, or they can be implemented usingdifferent control devices, for example a roller which can be rotated and pressedso that up, down and select functions would be mapped to it.Hardware solution may have some effect on the navigation functionality: forexample a long key press event can't be accomplished with a rotating device.Each softkey has a corresponding textual label on the bottom of the screen.The Edit key is the only key that can be used simultaneously with another keypress, for example, the combinations where any of the navigation keys arepressed while the Edit key is held down.See section Keypad functions in chapter Interaction style for more informationabout the usage of keys.Extra keysOther specific keys can be added to a product to emphasize or facilitate somefunctions. These extra keys could be used to control applications or hardware such asspoken commands, sound recording, and audio volume control.10