This handbook is derived from the online reference "Corrosion Handbook", bringing together the relevant information about corrosion protection and prevention for steels, one of the most widely used materials. It provides comprehensive information, including tabulated data and references, on the corrosion properties of the following materials: Unalloyed steels and cast steel, unalloyed cast iron, high-alloy cast iron, high-silicon cast iron, structural steels with up to 12% chromium, ferritic chromium steels with more than 12% chromium, ferritic-austenitic steels with more than 12% chromium, high-alloy multiphase steels, ferritic/perlitic-martensitic steels, ferritic-austenitic steels/duplex steels, austenitic chromium-nickel steels, austenitic chromium-nickel-molybdenum steels, austenitic chromium-nickel steels with special alloying additions, special iron-based alloys, and zinc. The following corrosive media are considered: Seawater, brackish water, industrial waste water, municipal waste water, drinking water, high-purity water.