Describir: Theory of corrosion and protection of metals :

 _____      _____                ___      ______   __   __    _  _      ___    
|  __ \\   |  ___||   ____      / _ \\   /_   _//  \ \\/ //  | \| ||   / _ \\  
| |  \ ||  | ||__    |    \\   | / \ ||  `-| |,-    \ ` //   |  ' ||  / //\ \\ 
| |__/ ||  | ||__    | [] ||   | \_/ ||    | ||      | ||    | .  || |  ___  ||
|_____//   |_____||  |  __//    \___//     |_||      |_||    |_|\_|| |_||  |_||
 -----`    `-----`   |_|`-`     `---`      `-`'      `-`'    `-` -`  `-`   `-` 
                     `-`