Monetization is the process of converting or establishing something into legal tener. It usually refers to the printing of banknotes by central banks, but things such as gold, silver and diamonds can also be monetized. Even intrinsically worthless items can be made into money, as long as they are difficult to make or acquire. Monetization may also refer to exchanging securities for currency, selling a possession, charging for something that used to be free or making money on a goods and services that were previously unprofitable.