Mark Rox calls himself a graffiti artist and most of his murals are located in Barcelona, Spain.(@pop.art.pov/Instagram) Optical illusions are all the rage on social ...

A stereogram optical illusion is a fascinating visual puzzle that hides a 3D image within a 2D pattern. At first glance, it appears to be a random collection of repeating designs or colourful dots.

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 ...

Illusion is derived from the Latin verb illudere, which means to mock or trick. Optical illusion pictures are designed to trick the human mind and are regarded as one of the simplest tests to ...