Its just an economic peripheral with USB connectivity. You just plug in the small scale like device in the USB drive and keep it on the bottom of the screen. Alas !!! your static laptop screen will become touch screen.
The company called Neonode have developed such a devise called "AirBar" which will use invisible light screen to enable this functionality to any computer screen. Any object come across the light field produced by the devise will trigger functioning of the AirBar. Hence besides direct touch of your finger it will work even with the touch of workers gloves or paint brush. It will respond to all gestures same as modern mobile of laptops having touch screen functionality like pinch, swipe, zoom and scroll.
Currently it will only work with 15.6" display having Windows 7, 8, 8.1 or 10. Neonode says they are working on Mac integrated option. So hopefully in the near future airbar become adaptable to most of our computer screens.
One of the main advantage of AirBar is that it does not require any software or stylus