Shanghai Stock Exchange's open-end fund sales system can provide efficient, automatic and integrated technical support for the subscription, purchase and redemption of open-end funds. Among them, subscription refers to the behavior of investors buying fund shares through SSE or through systems outside SSE during the raising period of open-end funds. Subscription refers to the behavior of investors buying fund shares during the duration of open-end funds. Redemption refers to the behavior that the fund share holder asks the fund manager to buy back the fund share according to the conditions stipulated in the fund contract.