Blockchain technology has great value and a great future. Smart contacts were invented a long time ago, thanks to the technology of blocki in 2008, they turned out to be implemented in 2013 thanks to Vitalik Buterin and Ethereum. Clever contracts based on cryptography, to contribute to better security than traditional contracts based on law, and to reduce other transaction costs associated with concluding contracts and possible legal costs. This is a unique and excellent technology that gives the world business to improve.