What is a galvanic cell? How do you decide the electrodes and solutions to be used in making a specific galvanic cell?

GALVANIC CELL
Galvanic cell is also known as “Voltaic cells “[12]. These cells are electrochemical cells. Within these cells instinctive electrode reaction occur which yield electric current which could be used to supply electric energy with the help of batteries or fuel cell [13]. Galvanic cells help directly to convert chemical reaction to electric energy [14].
In order to complete the electrical circuit, the two metal electrodes (which signifies galvanic cell) connected externally [15].
For specific galvanic cells, one metallic electrode should be more reactive so that it solubilize in an electrolyte, whereas the other metallic electrode have new deposition of metal on...