About Chainlink (LINK)
Chainlink is a decentralized oracle network. It aims to serve as a middleware between smart contracts on smart contracting platforms and external data sources, allowing smart contracts to securely access off-chain data feeds.
Through a decentralized network of independent oracle node operators, Chainlink provides a wide range of decentralized services to smart contracts including Price Feeds (financial market data used to power a large portion of the DeFi economy), verifiable randomness (enabling the creation of dynamic NFTs and fair on-chain gaming applications), proof of reserve (providing proofof off-chain collateral that is backing stablecoins and cross-chain tokens), the Keeper Network (transaction automation bots that provide autonomous DevOps services), and more. (Messari)
About Stacks (STX)
Stacks (formerly Blockstack) provides software for internet ownership, which includes infrastructure and developer tools to power a computing network and ecosystem for decentralized applications (dApps). Its focus is to replace the reliance on centralized cloud service providers and apps that harvest and monetize user information. The Stacks network allows users to directly own digital assets like usernames, domain names, computer programs, etc. On the Stacks blockchain, computing is done on the edges (i.e., client devices), and applications on the platform store data individually and use the blockchain only when necessary. (Messari)