I think by now most people are aware that Bitcoin operates on a Proof of Work (PoW) consensus, it's been in the spotlight for years, but more so in recent days due to the huge amount of energy it consumes for the purposes of consensus. Elon Musk recently back peddled on his pledge to offer Bitcoin for purchase of Teslas due (in part) to these sustainability concerns. Radix however, works on the basis of Delegated Proof of Stake (DPoS). Proof of Stake protocols, and in our case Delegated Proof of Stake, address many of the problems arising from PoW, principally the huge cost of hardware and energy consumption. Rather than consensus being determined by a network of nodes utilising energy intensive hardware, PoS consensus is determined by the total number of coins being staked. The more coins held, the higher the chances of being picked as a leader to determine the consensus of the ledger.
Since the operation of a validating node requires some technical expertise, significant stake and consistent uptime, Validator nodes such us Radstakes step in to provide dedicated server infrastructure to provide this service to holders of Radix (XRD).
Put simply, DPoS is a voting system, where holders of XRD can delegate to a trusted node to secure the network on their behalf. In exchange for staking and securing the network, rewards are emitted and distributed automatically to all stakers. For more details on Staking specifically on Radix, I have attached a handy link to the official Radix knowledgebase here: