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Later the word was used for processes of electrodeposition. Nowadays it typically means hot-dip galvanizing, a chemical process that is used to coat steel or iron with zinc. This is done to reduce corrosion (specifically rusting) of the ferrous item. The zinc coating prevents oxidation of the protected metal by forming a barrier. Zinc oxide is a fine white dust that (in contrast to iron oxide) does not cause a breakdown of the substrate's surface integrity as it is formed. Indeed the zinc oxide, if undisturbed, can act as a barrier to further oxidation, in a way similar to the protection afforded to aluminiumAluminium (or aluminum in North American English) is the chemical element in the periodic table with the symbol Al and atomic number 13. A silvery and ductile member of the poor metal group of elements, aluminium is found primarily as the ore bauxite and and stainless steelsIn metallurgy, stainless steel is defined1 as a ferrous alloy with a minimum of 10. 5% chromium content. Such steels have higher resistance to oxidation ( rust) and corrosion in several environments. It was invented in 1913, at the research laboratory of by their oxide layers. Hot dip gavanizing deposits a thick, robust layer that may be more than is necessary for the protection of the underlying metal in some applications. This is the case in automobileAn automobile usually called a car (an old word for carriage) or a truck is a wheeled vehicle that carries its own engine. Older terms include horseless carriage and motor car with "motor" referring to what is now usually called the engine. The act of ope bodies, where additional rust proofing paint will be applied. Here, a thiner form of galvanizing is applied by electroplatingElectroplating is the use of a solution of a metal salt, and an electrical direct current to coat an electrically conducting item with a layer of the metal making up the metal salt. Electro-deposition is the process by which electroplating is performed., called "electro-galvanized". Where the metal is not to be painted or is to be used in critical exposure conditions such as near salt water, "hot dip galvanized" is preferred for its long term durability. Galvanized nails are now usually electro-galvinized but these are greatly inferior to the hot diped kind, particularly when used in fences.

Obviously in some environments both mechanisms can be at work. For example, the traditional measure of a coating's effectiveness is resistance to a salt spray . Galvanization cannot protect surfaces subject to surface abrasion.