According to media reports today, Yang Bingbing, general manager of the Digital Finance Department of China Everbright Bank, said in an interview that the blockchain application is still not widely used, but the applicable fields are actually very wide, and there is still a certain gap. Although the blockchain is called a chain, each underlying technology of the blockchain has a lot to do with the data. For example, its distributed structure is to generate and update data. Its cryptographic algorithm is a mechanism for data confidentiality. Its asymmetric encryption is the transmission of data. Its smart contract is to use data. Each of its underlying technologies is closely related to data, which is why the blockchain is promising in the digital finance arena.