What is the most popular café in the world?

I'm curious, can you tell me what the most popular café in the world is? Is it a local spot in a bustling metropolis, or perhaps a cozy little nook in a quaint village? What sets this café apart from the rest, and what makes it so beloved by people from all walks of life? Is there a unique atmosphere, an unforgettable menu, or perhaps a special story behind it? I'm eager to learn more about this seemingly ubiquitous yet mysterious café that has captured the hearts of so many.