The most basic roti are a lot like flour tortillas, but they differ in a couple key details. The simplest and most common roti recipe is made from a mixture of low-protein, stoneground whole wheat flour known as atta, or chapati flour, water, salt, and oil. The Indian method for milling hard durum whole wheat generates heat through friction, and begins to break down some of the grain's protein. This "weakened" flour is ideal for breads like roti, that are typically kneaded by hand, and immediately rolled out to thin rounds. When rotis are rolled and cooked properly, they puff full of hot air, similar to pita bread, but far more delicate, with lots of toasty, whole wheaty flavor.