A baking or pizza stone is a thick, flat piece of natural stone or ceramic used for baking bread, pizza, and other baked goods. It is placed in the oven while it's preheating. This creates an extremely hot surface for even baking. The purpose of using a baking or pizza stone is to mimic the conditions of a traditional brick oven, which can reach higher temperatures than a regular oven at home and will provide a consistent heat source.