M, baking stones are terra cotta stones that you put in your oven, preheat for around an hour, and bake pizza on them.  They are also good for bread and pie crusts (but not cakes).  Do people only buy pizza from restaurants in Italy?

No, I often make it myself, but we usually bake it in round or rectangular metal pans, while in restaurants they’re made in special ovens with fire from wood…........