Participants (“nodes”) in decentralized, peer-to-peer networks provide the necessary computational resources that keep a network up and running. Proof-of-Stake (PoS) is the mechanism by which the various participants in Tezos reach consensus on the state of the blockchain. Unlike other PoS protocols, any stakeholder can participate in the consensus process in Tezos and be rewarded by the protocol itself for contributing to the security and stability of the network. Additionally, PoS is less costly than other consensus mechanisms and lowers the barriers to entry for involvement.
In PoS, a security deposit is required to participate in the consensus process. As in proof-of-work, the consensus protocol relies on an honest majority for its security which is incentivized directly by the Tezos protocol by penalizing dishonest behavior and rewarding honest behavior. If a participant behaves dishonestly, they can lose their deposit. Users who do not wish to participate directly in the consensus protocol have the option to delegate their rights to other users to participate on their behalf.