Oracle
Plain English
A service that feeds real-world information into the blockchain. Since smart contracts can’t access external data themselves (like stock prices or weather), oracles act as trusted bridges bringing that information on-chain so contracts can use it.
Technical
Third-party services providing external data to blockchains and smart contracts. Oracles solve the oracle problem - blockchains cannot natively access off-chain data. Decentralized oracle networks like Pyth and Chainlink aggregate data from multiple sources using cryptographic proofs and reputation systems. Critical for DeFi price feeds, cross-chain communication, and any contract requiring external state verification.