Bread is baked dough made from flour, water, salt and a leavening — humanity's oldest processed staple and, in its countless forms, the everyday carbohydrate of much of the world. At its simplest it is wheat flour and water worked into a dough, fermented so that gas inflates it, and baked until the inside sets into a soft, springy crumb and the outside browns into a crisp, aromatic crust. That single template branches into endless breads: tall sandwich loaves and rustic sourdough boules, lean French baguettes, dense dark ryes, soft enriched brioche and the unleavened flatbreads — chapati, tortilla, pita — that feed billions. Good bread smells warm, malty and faintly nutty, with a toasty, popcorn-like crust note over a tangy or yeasty interior, and it tastes mildly sweet and gently salty.