Abstract:Block chain, as a network database, a book that uses block records to record transaction information, is essentially a distributed public ledger, namely, a series of chained data structures constructed on the basis of cryptography and ensured not tamperable or forgeable. Block chain is not a single technology or framework, but a distributed reconfiguration of technologies and platforms in the Internet age. Block chain technology is a technique for encrypting and time-stamping data, forming data chains according to time stamp order, and storing data in a distributed manner. This technology covers a variety of cutting-edge computer technologies including point-to-point transmission, consensus mechanism, encryption algorithm, distributed storage, and has the characteristics of decentralization, non-tampering, traceability and collective maintenance. With these characteristics, block chain technology is especially effective in credit management, cross-border payment and settlement, supply chain finance, unified user account system, data sharing platform, asset securitization, legal digital currency, financial market services, bank asset trustship systems, etc. Although block chain technology has problems such as low update frequencies and difficult supervision, once it breaks through in many technical and non-technical areas, block chain technology will nurture and innovate various underlying technology platforms, and profoundly change the ecosystem in many industries, and then trigger major changes in the entire economic and social life.