Puff pastry was invented by a French apprentice named Claude Gelée. He forgot to add butter to his dough. He wrapped it inside instead. He invented something better on accident.
It’s also called pâte feuilletée. Say that three times fast. It means “leafy paste.” Fitting, because it flakes like autumn leaves.
In the 1600s, it was used to make vol-au-vents (fancy pastry cups). Those things are just puff pastry circles. You can make them right now. Impress your cat.