A broad market is a group of vendors and individuals who are associated with other vendors and individuals to buy and sell certain goods. The size of the market, the size of the market, is the number of buyers. But in order to better future, we must expand the definition of the word "profit", the economic benefits and social benefits are included, and understand that block chain itself is a social innovation of technical solutions. (1) spiritual gain -- spiritual satisfaction; HM, Liverpool Famous British economist hicks and others argue that the above theory did not consider the factor of income, and therefore unable to determine the level of interest rates, in 1937, and puts forward the is-lm model on the basis of general equilibrium theory. It establishes a theory of interest rates and income at the same time that the four factors of savings and investment, money supply and monetary demand interact.