The Spinning Dancer is an optical illusion that appears to be a female figure spinning clockwise or counterclockwise. The figure appears to be spinning, but it is impossible to tell which direction she is spinning in. The illusion has been used to test the viewer's perception of motion and
The Spinning Dancer, also known as the Silhouette Illusion, is a kinetic, bistable, animated optical illusion originally distributed as a GIF animation showing a silhouette of a pirouetting female dancer. The illusion, created in 2003 by Japanese web designer Nobuyuki Kayahara, involves the apparent direction of motion of the figure. Some observers initially see the figure as spinning clockwise and some counterclockwise. Additionally, some may see the figure suddenly spin in the opposite direction.