Glossary
Randomness Beacon
A service that publishes fresh, unpredictable random values on a regular schedule — used by protocols that need shared, verifiable randomness.
A randomness beacon publishes a sequence of random values, each verifiable, on a regular schedule. The values are unpredictable in advance and unbiasable in retrospect, so a smart contract can commit to using "the beacon's next output" as a fair source of randomness.
Beacons can be VRF-based (Chainlink, Algorand), threshold-signature
based (drand), or extracted from the consensus protocol itself
(Ethereum's RANDAO post-Merge, with prevRandao available as
block.prevrandao).