Etch A Sketch is a mechanical drawing toy invented by French inventor André Cassagnes and subsequently manufactured by the Ohio Art Company. An Etch A Sketch has a thick, flat gray screen in a red plastic frame. There are two knobs on the front of the frame in the lower corners. Twisting the knobs moves a stylus that displaces aluminium powder on the back of the screen, leaving a solid line.
The knobs create lineographic images. The left control moves the stylus horizontally, and the right one moves it vertically.
LINK Etch A Sketch