# Blockchain Oracles > Explained Under 5 mins **Published by:** [Everything Blockchain](https://paragraph.com/@everythingblockchain.com/) **Published on:** 2023-05-09 **Categories:** blockchain, web3, defi, oracles, cryptocurrency, smart contracts, videos **URL:** https://paragraph.com/@everythingblockchain.com/blockchain-oracles-explained ## Content Blockchains and smart contracts are self-contained closed systems that can't access data external to their network. However, many contractual agreements require off-chain data to facilitate their execution. So, how do these self-contained systems access off-chain data? The answer is Oracles. Oracles can retrieve data from various sources, including APIs, websites, and sensors, and then provide this data to the smart contract to trigger the appropriate actions. This allows for more complex and dynamic smart contracts that can interact with real-world events and information. Without oracles, smart contracts would have minimal use, and DeFi would not be where it is today. Watch the video to learn more about Oracles and the various types. If you find this helpful, please support through subscribing and following. Everythingblockchain 🧐 - Freethinkers, Writers ✍, Blockchain explorers 🔭 In pursuit of simplifying the different blocks of the chain metaverse Socials Twitter, Medium, Youtube, Reddit, Substack The information provided through this work is intended solely for educational purposes and must not be treated as investment advice. Any lapses in presenting any of the information correctly are ours alone. We disclaim any liability associated with the use of this content. ## Publication Information - [Everything Blockchain](https://paragraph.com/@everythingblockchain.com/): Publication homepage - [All Posts](https://paragraph.com/@everythingblockchain.com/): More posts from this publication - [RSS Feed](https://api.paragraph.com/blogs/rss/@everythingblockchain.com): Subscribe to updates - [Twitter](https://twitter.com/EverythingB0x): Follow on Twitter ## Optional - [Collect as NFT](https://paragraph.com/@everythingblockchain.com/blockchain-oracles-explained): Support the author by collecting this post - [View Collectors](https://paragraph.com/@everythingblockchain.com/blockchain-oracles-explained/collectors): See who has collected this post