Chainlink (LINK) is a decentralised oracle network that connects smart contracts to real world data. Blockchains cannot access outside information on their own, so applications that need prices, sports results, weather or other data rely on oracles. Chainlink collects data from many independent node operators and delivers it on chain, which reduces the risk of a single point of failure. Co-founded by Sergey Nazarov and Steve Ellis, the project launched in 2017. It supplies price feeds to many DeFi protocols and also offers cross chain messaging and proof of reserve tools. LINK is used to pay node operators and to help secure the network.