Question

what is cathodic protection of corrosion

Answer 1

Cathodic protection  is a technique used to control the corrosion of a metal surface by making it the cathode of an electrochemical cell

Answer 2

$\textbf{Cathodic Protection }$:

Preventing the corrosion of a metal by connecting it to a more reactive metal is called Catholic protection of metal.

For Example, when iron is connected to a piece of Magnesium, it doesn't get corroded as long as Magnesium is present.