I won't talk about academic things. Let's talk about what is popular today.
First of all, what is a bank? Banks used to be called banks, which are shops that help people manage storage, transportation, transfer, exchange (exchange), leasing and so on. In a word, what banks do is all about money. Bankers are the shopkeepers and big boys in the bank (not counting the boys who pour tea), that is, the guys who help people look after, count and make money.
Later, banks did more and more business, and banks classified them according to the customers they served.
Personal services for ordinary people are called "retail banks" or "personal banks"; Those who serve "big companies" and "big institutions" are called "wholesale banks" or "commercial banks".
It's easier said than done for ordinary people. It's nothing more than setting up a deposit, a loan and a credit card. So those bankers who work in "retail banks" or "personal banks" are basically things that mothers do all day. But they must be very rigorous and accurate. Whoever is short of a penny is in a hurry with you!
But corporate customers are different. It has other needs besides the services that ordinary people need.
If the company wants to develop, it must have funds.
When the money is not enough, we must find a way to "do" it.
"Making money" (Chinese is not so good), in English, is to raise money or raise funds.
"Making money" is nothing more than "equity financing" and "debt financing". No matter what kind of financing, you use other people's money (OPM or even ass).
Therefore, investment banks help others make money. Why do you sound like a liar? It's best to say it in English (which is why all investment banks use English instead of Chinese):
Investment banking or online banking is a term used to describe the business of raising funds for companies.
Do you understand now?