This Optical Illusion Reveals a Hidden Number – and Everyone Sees It Differently

Imagine a gray and black striped circle, an image that at first glance seems innocuous. However, it hides a mystery that fascinates a large part of Internet users: a number is hidden in this circle, but only a trained eye can detect it. This phenomenon is not just a simple entertainment: it is a real test of your sensitivity to contrast. But why can such a simple image pose so many difficulties?
A disturbing visual experience