The yellow resembles the corner (a yellow cube) of a checkerd board when viewd from overhead. Optical illusion + Modern art.
Yes, no, maybe?
Don't see it?
Expand picture by placing cursor on photo and left click the mouse, continue with a click each time a new sized picture comes up. Keep expanding until photo fills the screen, then you'll see the full optical effect with the glossy finish, intersecting lines and the cube. The seperation line for the colors really 'pops out' when expanded.