An optical illusion shared on social media by Kiwi Nanogirl has gone viral.
New Zealand-based nanotech engineer Dr Michelle Dickinson shared an image of what seem to be black and white stripes, however with effort a hidden animal appears.
"You can only see this optical illusion if you shake your head," she wrote on Twitter.
If you can't see the animal straight away by shaking your head back and forth, you may need to step further away from your computer or iPhone.
After embarrassing yourself at work or home, you might find that you can see a cat.
Many on Twitter shared their thoughts on the the optical illusion.
"Omg that's amazing," on commented.
Another wrote: "Here I am shaking my head like a crazy person at my work desk."
Others shared advice saying "squinting works too" while another suggested "turning your screen away from you at an angle".
Some claimed they could see the cat "straight away" without shaking their head.