The Droste effect…

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The Droste effect, as seen in the picture above, is a visual form of recursion. Cool huh?

From Wikipedia:

“An image exhibiting the Droste effect depicts a smaller version of itself in a place where a similar picture would realistically be expected to appear. This smaller version then depicts an even smaller version of itself in the same place, and so on.

The effect is named after the image on the tins and boxes of Droste powder, one of the main Dutch brands, which displayed a nurse carrying a serving tray with a cup of hot chocolate and a box with the same image. This image, introduced in 1904 and maintained for decades with slight variations, became a household notion.”