The concept of Bitcoin was first proposed by Satoshi Nakamoto in 2008. It designed and released open source software based on Satoshi Nakamoto's ideas and constructed the P2P network on it. Bitcoin is a P2P form of digital currency. Point-to-point transmission means a decentralized payment system. Unlike most currencies, Bitcoin does not rely on specific currency institutions to issue. It is generated through a large number of calculations based on specific algorithms. The Bitcoin economy uses a distributed database composed of many nodes in the entire p2p network to confirm and record all transaction behaviors. And use the design of cryptography to ensure the security of all aspects of currency circulation. The decentralized nature of p2p and the algorithm itself can ensure that the value of the currency cannot be manipulated through the large-scale production of Bitcoin. The design based on cryptography allows Bitcoin to be transferred or paid only by the real owner. This also ensures the anonymity of currency ownership and circulation transactions. The biggest difference between Bitcoin and other virtual currencies is that its total number is very limited and it is extremely scarce. The currency system used to have no more than 10.5 million in 4 years, and the total number after that will be permanently limited to 21 million.