User:A at Chainlink/ChainlinkDraft

Chainlink is a Chainlink decentralized blockchain oracle network that allows off-chain data and computation to be brought securely onto blockchains and interact with smart contracts.

History
Chainlink was created in 2017 by Sergey Nazarov and Steve Ellis, who co-authored a white paper introducing the Chainlink protocol and network with Cornell University professor Ari Juels the same year. Chainlink acts as a "bridge" between a blockchain and off-chain environments. The network is used by smart contracts and was formally launched in 2019.

In 2018, Chainlink integrated Town Crier, a trusted execution environment-based blockchain oracle that Juels also worked on. Town Crier connects the Ethereum blockchain with web sources that use HTTPS. In 2020, Chainlink integrated DECO, a Cornell project co-created by Juels. DECO is a protocol that uses zero-knowledge proofs to allow users to prove information is true to a blockchain oracle without revealing sensitive information, such as birth dates.

Chainlink published a second white paper in April 2021. That paper, Chainlink 2.0: Next Steps in the Evolution of Decentralized Oracle Networks, detailed a vision for expanding the role and capabilities of decentralized oracle networks to include hybrid smart contracts, which utilize on-chain code and off-chain services provided by oracle networks. More than 650 entities have integrated with Chainlink as of July 2021, including the Associated Press, Google, and Deutsche Telekom.

Technology
Chainlink's decentralized oracle network is an open-source technology infrastructure that allows any blockchain to securely connect to off-chain data and computation resources. The network nodes fetch, validate, and deliver data from multiple sources onto blockchains to execute smart contracts. Node operators are compensated with the network's native cryptocurrency, LINK. The LINK token is compatible with the Ethereum ERC20 and ERC677 token standards.

Additional functionality
In addition to the transfer of external information to a blockchain, Chainlink can also be used for several different off-chain computation functions, including a verifiable random function (VRF), data and price feeds, programmable external adapters, and Keepers.

Chainlink's VRF can be used for random number generation which can be used in decentralized gaming and in the minting of NFTs. ZDNet reported the verifiability of the random number generation ensures the in-game results are tamper-proof.

The data and price feeds supported by the Chainlink network are aggregated data streams that include market prices and conversion rates. Other uses for the data feeds include bringing weather information on-chain for parametric crop insurance as well as election data.

Chainlink nodes can also connect to external adapters, allowing smart contracts to use computing power not directly on a blockchain network. These software extensions allow a node operator to allow smart contracts to use external APIs and perform other tasks independent of the blockchain, such as connecting to payment software.

Keepers are a service that automates smart contracts and reduces manual maintenance for developers. Decrypt reported that Keepers can automate token minting, harvesting yields from vaults, and the liquidation of undercollateralized loans.