According to the China Financial Information Network, on December 12, the theoretical learning center group of the Chengguan District Committee of Lanzhou City held a special lecture. Guo Xinghua, chief expert of the blockchain of China Economic Information Agency Xinhua Finance and China Financial Information Network said in a speech, The word "chain" comes from the description of the underlying data structure of bitcoin. The data in the bitcoin system is packaged by miners to form blocks, which are connected to each other by hash values. It is very similar to the "chain list" structure in programming, so it is called "chain" Blockchain. " At present, the connotation of the blockchain has been expanded layer by layer. The simple "block" and "chain" can no longer explain its essence, which is why the concept of the blockchain is difficult to grasp. The development of blockchain technology is divided into three stages, the digital currency stage, the smart contract stage, and the extended application stage. Guo Xinghua also said that at present, the blockchain projects promoted by governments around the world mainly involve financial, government archives, digital asset management, voting, government procurement, land certification / real estate registration, medical health and other fields.