Forgive me but I'm totally ignorant on this regard. Given that I may not be able to ask the right question.
AFAIK, they differ in terms of how dividends are being paid and by how much. But do common stocks and preferred stocks have any differences in terms of the percentage of the company per unit they are representing? If they represent the same amount of shares or percentage of the company per unit, shouldn't they be sold at the same price and should be paying the same amount of dividends (or equivalent profit) per unit?
I'm simply trying to understand why there has to be a distinction between preferred stocks and common stocks. (i.e., why do we have preferred stocks and common stocks instead of just simply common stocks for simplicity's sake?)