Necker cube

Okay, kiddo! Have you ever played with those little boxes on paper that are like two squares stacked on top of each other? They're called a "necker cube."

The necker cube is an optical illusion that tricks our brains into seeing two different 3D objects at the same time, even though they're really just flat on paper. It's like a magic trick for our brains!

The cube looks like a square box, but it's missing one side. This means that we can see either the top and front sides of the box, or the side and bottom sides of the box, but we can't see both at the same time.

Some people might see the box with the top and front sides facing up, while others might see the box with the side and bottom faces facing up. And, some people might even switch back and forth between the two!

So, even though the box is flat on paper, our brains are trying to make sense of the image by seeing two different 3D objects at the same time. It's like trying to look at a picture of a beach and hearing the sound of waves crashing in your head - your brain is filling in the gaps!

Pretty cool, huh? Optical illusions like the necker cube show us how powerful our brains are at interpreting the world around us.