The primary ingredient in bread is flour, typically made from ground wheat grains. Flour provides the structure and texture of bread and comes in various types, including all-purpose, whole wheat, and bread flour, each contributing unique qualities to the final product. When mixed with water, yeast, and other ingredients, the proteins in flour—mainly gluten—form a network that traps air bubbles, allowing the bread to rise during fermentation. This gluten formation is crucial for the bread's chewiness and overall texture. Flour's versatility makes it an essential component in many baked goods beyond just bread, including pastries and cakes.