The Snake and Rope
Classic metaphor for misperception of reality.
A rope seen in dim light is mistaken for a snake, causing fear. When light reveals the rope, the snake and fear vanish. Similarly, when knowledge arises, maya disappears.
Just as the snake superimposed on the rope disappears when the rope is known, so the world disappears when Brahman is known.
This metaphor illustrates how reality is misperceived.
Vedantic Tradition