As discussed in , Smart Contracts, Oracles are real-world data feeds into smart contracts.
There are various services available in order to provide Oracles for smart contracts.
Connecting Smart Contracts to the Real World (Part 2)
This is especially useful if the smart contract needs, for example, live http://www.oraclize.it/ prices from a third-party source or any other real-life data, such as weather conditions in a particular city.
There are many use cases where Oracles can provide a trusted data feed to smart contracts in order to enable them to make decisions according to real-life events.
Oraclize makes it easier for smart contracts to access the Internet in order to get the required data.
In order to utilize Oraclize on Ethereum, a transaction needs to be sent to the Oraclize contract along with the appropriate payment and the query.
As a result, Oraclize will retrieve the results based on the query provided in the request transaction and send it back to the contract address.
Once the transaction is sent back to the contract, the callback method or fall back function will be called.
Why This Matters for Blockchain Technology
At a practical level in solidity, first, the Oraclize library needs to be imported and then all methods that have been inherited from it can be used.
Currently, Oraclize is available to be used only on the PrivateNet (Ropsten) and Live Main Net Ethereum blockchain.
Oraclize processing can be visualized. diagram: Oraclize data flow On top we have the Ethereum blockchain and smart contract, to which Oraclize talks via a secure mechanism.
Oraclize can request data from external data sources, which can be fed into Oraclize, which can then be sent down to Ethereum blockchain.
Key Points to Remember
- Oracles As discussed in , Smart Contracts, Oracles are real-world data feeds into smart contracts.
- There are various services available in order to provide Oracles for smart contracts.
- This is especially useful if the smart contract needs, for example, live http://www.oraclize.it/ prices from a third-party source or any other real-life data, such as weather conditions in a particular city.
- There are many use cases where Oracles can provide a trusted data feed to smart contracts in order to enable them to make decisions according to real-life events.
Going Deeper: Advanced Concepts
The answer comes with a TLSNotary proof ensuring the integrity and
various services available in order to provide Oracles for smart contracts. A rather prominent one is Oraclize, which is available at . This is especially useful if the smart contract needs, for example, live http://www.oraclize.it/ prices from a third-party source or any other real-life data, such as weather conditions in a particular city. There are many use cases where Oracles can provide a trusted data feed to smart contracts in order to enable them to make decisions according to real-life events. Oraclize makes it easier for smart contracts to access the Internet in order to get the required data. In order to utilize Oraclize on Ethereum, a transaction needs to be sent to the Oraclize contract along with the appropriate payment and the query. As a result, Oraclize will retrieve the results based on the query provided in the request transaction and send it back to the contract address. Once the transaction is sent back to the contract, the callback method or fall back function will be called. At a practical level in solidity, first, the Oraclize library needs to be imported and then all methods that have been inherited from it can be used. Currently, Oraclize is available to be used only on the PrivateNet (Ropsten) and Live Main Net Ethereum blockchain. Oraclize processing can be visualized. diagram: Oraclize data flow On top we have the Ethereum blockchain and smart contract, to which Oraclize talks via a secure mechanism. Oraclize can request data from external data sources, which can be fed into Oraclize, which can then be sent down to Ethereum blockchain. The answer comes with a TLSNotary proof ensuring the integrity and
Conclusion
Oracles represents one of the many innovative layers that make blockchain technology so powerful and transformative. As distributed systems continue to evolve, a solid understanding of these core concepts becomes increasingly valuable — not just for developers, but for anyone building, investing in, or working alongside blockchain-powered systems.
Whether you are just starting your blockchain journey or deepening existing expertise, mastering these fundamentals gives you the tools to think clearly about decentralized systems and make smarter decisions in this rapidly evolving space.