Baking is a method of preparing food that uses dry heat, normally in an oven, but can also be done in hot ashes, or on hot stones. The most common baked item is bread but many other types of foods are baked. (extracted from Wikipedia)

The baking process alters the product completely, from a dough to a bread, through many biochemical processes. The most visual one is the Maillard Reaction that occurs in the outer layer of the bread's surface. This reaction changes the color, taste and aroma of the bread (or any other baked good) through a series of interactions of the bread's ingredients with the heat from the oven.