Galvanizing
Galvanizing, or galvanising, depending on where you are when you read this, is the name for various processes that is used to deposit zinc onto the surface of a steel article.
There are several types of galvanizing, but they are all a process of coating steel with zinc.This provides a "sacrificial layer" that protects the steel below from corrosion.
Galvanized steel lasts much longer than ungalvanized steel without corroding, but it's still not ideal for use very close to salt water or in heavy industrial environments, where chemicals or salt in the air will speed up rusting and corrosion.