Pure Proof of Stake (PPoS) is a consensus mechanism used in blockchain networks to validate transactions and create new blocks. In PPoS, validators are chosen to create new blocks based on the number of coins they hold and are willing to "stake" as collateral. This system encourages users to hold onto their coins, as having more coins increases their chances of being selected as a validator. Unlike Proof of Work, which requires significant computational power and energy consumption, PPoS is more energy-efficient. It allows for faster transaction processing and greater scalability, making it an attractive option for blockchain projects aiming for sustainability and efficiency.