While new optical illusions go viral all the time, here are some of the most famous illusions that have kept us scratching our heads for years.

Optical illusions occur naturally in different habitats and conditions across the world. Cloud formations can sometimes make it seem like there's an ocean or a UFO in the sky. Whether it is salt flats ...

The famous Ebbinghaus illusion, named for its discoverer, the German psychologist Hermann Ebbinghaus (1850–1909). Despite appearances, the two orange circles are the same size. Have you ever looked at ...

Optical Illusion: We are back with another one of our illusions- ONLY, this time, it is a bit different than the rest! Today’s illusion is literally an ‘illusion’ that you have to solve- or figure out ...

Everyone loves an optical illusion — even if they leave us completely stumped — and they're all around us in the natural world. From an underwater waterfall in the Indian Ocean to a surrealist scene ...