Stainless steel cookware has many advantages: it doesn't react (as does aluminum) with acidic or alkaline foods; it is corrosion-resistant, strong and easy to clean; and it doesn't scratch, pit or dent easily. The main disadvantage of stainless steel is its poor heat conductivity, a problem somewhat reduced in heavy, well-made pans. The best of all possible worlds is achieved by "sandwiched" cookware, with a layer of either aluminum or copper (both excellent at conducting heat) between two thin sheets of stainless steel.