Puff pastry and croissant are both flaky pastry doughs, but the difference lies in the ingredients used and the method of preparation. Puff pastry is made with just flour, butter, and water, whereas croissant dough includes yeast, milk, and sugar in addition to the basic ingredients. The process of making croissant dough includes folding and rolling the dough several times with a layer of butter, resulting in a slightly sweet and buttery taste. Meanwhile, puff pastry is made by layering thin sheets of dough and butter, and doesn’t typically contain sugar or yeast, resulting in a more neutral flavor. Croissants are also typically shaped into crescent shapes and are curved, while puff pastry can be cut into various shapes and used for savory or sweet dishes.