Skinput is a technology developed by researchers at Microsoft that allows a user's skin to be used as an input surface. It uses sensors in an armband to detect vibrations from taps on the skin and determine their location. The armband also projects a keyboard or other interface onto the user's arm. By matching tap locations to the projected interface, Skinput can interpret gestures and taps as commands to control devices like phones or music players without directly touching a screen. It aims to provide a more natural input method that does not require looking at or directly interacting with a device.