ELECTROPLATINGIt is the coating of one metal over the other which is called electroplating. It is done for few reasons to benefit us:

1.  Resistance to corrosion and increased life span
2. Provision of insulation
3. Better appearance for e.g. chrome, nickel or silver can produce a mirror like finish

Resistance to corrosion and increased life span: A coat of one less valuable metal on a more valuable metal can be very beneficial.  For example if zinc is electroplated on iron then it would protect iron from getting corroded and would ensure proper usage.

Provision of insulation: Insulating materials can be electroplated for safety of living organisms. Plastic for example can be electroplated on copper or aluminum for protection from shocks.

Better appearance: this one of the most common method used for everyday life coating. Electroplating of silver, chrome or nickel protects the base metal from corrosion, or scratches as well as provides a shiny attractive appearance for decorations or jewelry. 

For Electroplating , Extraction of metals and Electrolysis hair removal treatment