An optical illusion is a visual phenomenon in which our perception of an image differs from objective reality. This image is ...

Optical illusions are older than you think. The first optical illusions date back to 20,000 BC and took the form of cave sculptings. Nowadays they are found all over the place – on screens, in books ...

When you buy through links on our articles, Future and its syndication partners may earn a commission. Credit: FOTOKITA via Getty Images I'll start with a warning. If you're easily spooked then this ...