Proof of Stake (PoS) has become one of the mainstream consensus algorithms. Since 2012, with the combined efforts of different researchers and teams, many technical problems have been solved, such as Nothing at Stake, Long Range Attack, etc. By 2018, the PoS consensus algorithm gradually matured. In June of the same year, PoS (PoS-like) projects represented by EOS and Tezos, began to go live, marking the beginning of a new generation of PoS consensus-driven technologies. Over the next two years of development, PoS has ushered in a golden development period. In 2020, representatives of new public chains like Polkadot, Near, Solana, and Celo all adopted PoS as their consensus algorithm of choice.