Proof of Stake is a method of preventing any one person from having unfair influence as a validator node in a decentralized blockchain or DLT network by using the native token of the network as a scarce resource. Proof of Stake is the most common alternative to Proof of Work. PoS systems were designed to solve some of the emerging problems and the enormous waste of energy called by PoW “mining” on PoW-based blockchains such as Bitcoin. Generally, PoS works by node-runners “staking” a quantity of the network’s token, locking it to earn a role in network consensus participation. These staked node-runners then receive mining-like incentive rewards for having done so.
Delegated Proof of Stake (or DPoS) is a particular type of PoS where any holder of the network’s token may “delegate” a stake of tokens to node-runners to help increase network security by increasing the amount of tokens that a Sybil attacker must acquire. These delegators also share in network incentive rewards.
In DPoS, a delegator of tokens does not lose control of their tokens or transfer them to the validator. The network protocol merely locks the tokens until they are unstaked by the owner.
DPoS is the Sybil protection mechanism that Radix uses, and it is the basis of XRD staking on the Radix network. You can learn all about staking on Radix here: Start Here! Radix Staking Introduction