Oracles

“A blockchain oracle is secure middleware that facilitates communication between blockchains and any off-chain system, including data providers, web APIs, enterprise backends, cloud providers, IoT devices, e-signatures, payment systems, other blockchains, and more.” - (Source: What is the Blockchain Oracle Problem? (https://blog.chain.link/what-is-the-blockchain-oracle-problem/))

Oracles maintain a critical role in crypto infrastructure as a means of connecting smart contracts to off-chain data