The primary ingredient in traditional bread is flour, which is typically made from wheat. The flour is mixed with water, yeast, and salt to create dough, which is then kneaded, left to rise, and baked. Different types of flour can be used to create various bread textures and flavors, such as whole wheat, rye, or gluten-free options. Yeast plays a crucial role in fermentation, helping the dough to rise and develop a light, airy texture. Overall, the combination of flour and the fermentation process is central to bread-making.