Oracles are third-party services that provide real-world information to smart contracts. In short, oracles help establish communication between the physical world and blockchains. As smart contracts cannot access off-chain data, it makes blockchain oracles an essential part of the ecosystem. But, the external information is vital to executing the agreement in several cases. While the data stored on the blockchain is ‘on-chain,’ the external data to the blockchain is known as ‘off-chain.’ Bloc...