"There has been good evidence to support the fact thatthrough touching, manipulating, exploring and testing, children find out and learn about the world around them" - Madhur Khandelwal, Ali Mazalek. (2007)
Interfaces are merely graphical today! A PC is usually operated via a mouse and a keyboard, but these do not operate the PC directly. The mouse controls the PC via a small arrow on your screen. Moving the mouse does not by itself affect the behavior of the computer, it is the (graphic) arrow, its position and function connected with this place that determine the behavior of the computer. This is called a graphical interface.