The primary ingredient used in baking bread is flour, typically derived from wheat. When mixed with water, flour forms a dough that can rise through the process of fermentation, where yeast consumes sugars and produces carbon dioxide. This gas causes the dough to expand and develop its texture. Other essential ingredients that often accompany flour in bread-making include yeast, salt, and sometimes sugar or fats. Each of these contributes to the flavor, texture, and appearance of the final bread product. Without flour, the bread would lack structure and density, making it a crucial component in the baking process.