Chainlink is an Ethereum-based platform serves as an intermediate stage between smart contracts and external data. Another word, this is a version of ‘oracle.’ The project was launched by SmartContract company established in 2014. The company cooperates with the interbank data transfer and payment system SWIFT, which covers 11 thousand banks worldwide. The main aim of the project is to optimize and expand the usage of smart contracts and to reduce the possibility of information fault or inaccuracy. Oracle nodes receive real-world data, proceed it through the network and take it to the blockchain. Oracle operators that contribute to the Chainlink harvesting and transmission have a reward in Chainlink ERC-20 tokens. On 1st, June 2019, Chainlink launched its mainnet on Ethereum platform.