1. There is a government agency called the Central Bank, which is responsible for printing money (in fact, it has no printing machine, only some electronic accounts, just adding numbers to it).
After printing, it lent the money to the bank. Banks lend money to individuals and industrial and commercial enterprises, and money enters the market. It's that simple. Of course, there are other ways. For example, the central bank will also directly use the printed money to buy things, but generally only gold, foreign exchange, national debt and so on. After shopping, the money is spent and the money enters the market.
3, the bank to recover the loan, and then return the money to the central bank, this is to withdraw money; The central bank sells things in the market, such as gold and government bonds, and it also collects money.
4, there is a special thing, banks can enlarge the amount of money:
Because most of the money lent by the bank will eventually flow back to the bank, and then the bank will leave a small part for depositors to withdraw money, then lend it out, and then wait for the money to flow back, leave a small part, and then lend it out ... so that the currency circulating in the market will be many times larger than the currency sent by the central bank. This is the "currency derivative" of banks. Therefore, the central bank's currency issuance and withdrawal will increase or decrease the currency circulation by several times. Prices generally rise, indicating that there is too much money in circulation, and the central bank will withdraw money; On the contrary, it will issue money again.
So, can you understand?