Blockchain technology has been associated with many applications including the cryptocurrency. Ten years ago, cryptocurrency were invented as competitor for the traditional money and banking system. The value of the so-call cryptocurrency is limited to several factors including social acceptability. In this study, we concentrated on two different types of blockchain techniques namely Ethereum and Bitcoin. The differences and features of everyone is being discussed. From the other hand, we reviewed the state of the art technology that represented by forecasting system for the cryptocurrency value.