Funds can be divided into broad sense and narrow sense. Broadly speaking, they refer to a certain amount of funds set up for a certain purpose, such as trust and investment funds, provident funds, retirement funds and so on. In a narrow sense, they refer to funds with specific purposes and uses. Usually, funds mainly refer to securities investment funds.

According to whether fund units can be increased or redeemed, they can be divided into open-end funds and closed-end funds. Open-end funds are not traded on the market (as the case may be), but are purchased and redeemed by banks, brokers and fund companies, and the fund scale is not fixed; Closed-end funds have a fixed duration and are generally listed and traded on the stock exchange. Investors buy and sell fund shares through the secondary market.

According to different organizational forms, it can be divided into corporate funds and contractual funds. A fund is established by issuing fund shares to establish an investment fund company, which is usually called a corporate fund; The establishment of fund managers, fund custodians and investors through fund contracts is usually called contractual funds. China's securities investment funds are all contractual funds.