The principle is that the POS machine reads the information of the bank card, sends the transaction information to the information center of China UnionPay, which processes it, communicates with the issuing bank and the acquiring institution, and then returns the approved transaction information to the POS machine, prints the shopping list, and the cardholder signs it, and the money in the bank card will be transferred to the account bound by the merchant.

Said a lot, the actual process of more than ten seconds. The role of UnionPay is the core. It integrates multiple issuers and acquiring institutions, and realizes the instant communication of data.

The acquiring bank is the acquiring institution, which used to be the exclusive business of banks. Later, because banks could not cover many small and medium-sized Wechat business, the central bank sent 200 acquiring photos to some private technology and financial service companies, which are third-party acquiring institutions, such as Lacarra, Remittance World, Qian Bao and Shengfutong, and their businesses are equally safe and reliable.