oracle

Oracles are a bridge between the EVM (Ethereum Virtual Machine) and the outside world. Decentralized Applications (DApps) use Oracles to view external data feeds, such as prices, or generate random numbers. The "oracle" eye represents a DApp's view outside the blockchain. The pupil contains the Chainlink VRFCoordinator.sol contract source code, an Oracle that gives DApps the ability to generate random numbers on-chain.