Orbitium uses a consensus system called Delegated Proof-of-Stake (D-POS), which is a more energy-efficient and cost-effective alternative to Bitcoin's consensus system. D-POS involves Validators and Delegators, who work together to secure the blockchain.
Validators are responsible for validating transactions and producing new blocks, while Delegators (stakers) can delegate their voting power to Validators they trust. This helps to ensure the security and stability of the network.