The Unconditional Guru

Here are the five ways:-

1. Paint the surface of metal.
2. Oil the surface of metal or keep it covered with grease.
3. Electroplating it with a less reactive metal will keep it safe.
4. Galvanisation that is covering it with Zinc metal it is also called sacrificial protection.
5. Making it cathode, most of the underground pipes are kept safe by connecting them to the negative terminal and very small amount of current flows from it.