How is electroplating used to protect metals from corrosion?

Electroplating is the application of a metal coating to various kinds of products. Coated with corrosion-resistant metals. For example Cr, Ni, Zn, Sn and others. For example, a good old Soviet car Volga was covered with three layers of Cu-Ni-Cr. Through trial and error, we came to the conclusion that it is three layers that help against corrosion most effectively. There are two ways to protect it: cathodic and anodic. One way protects mechanically and the other electrochemically.