One type of motion illusion is a type of optical illusion in which a static image appears to be moving due to the cognitive effects of interacting color contrasts and shape position.

To properly view this effect, click the image above to see the full sized version.

The Ebbinghaus illusion is an optical illusion of relative size perception. In the best-known version of the illusion, two circles of identical size are placed near to each other and one is surrounded by large circles while the other is surrounded by small circles; the first central circle then appears smaller than the second central circle.

The Kanizsa triangle is an optical illusion first described by the Italian psychologist Gaetano Kanizsa in 1955. In the image above, a white equilateral triangle is perceived, but in fact none is drawn.