Common oracle design and implementation

## Summary
> Please give a short summary of this research topic.

Given that the blockchain operates within a closed environment, protocols requiring real-world data often rely on oracles as intermediaries. Oracles serve as the bridge between external data sources and smart contracts. What are the existing oracle design patterns, and how do they differ from one another?

## Description
> Please provide a detailed description to the topic.

Numerous protocols rely on oracles to calculate asset prices, commonly referred to as "price feed oracles." Two prevalent types are on-chain oracles, such as the TWAP oracle used in Uniswap V2, and off-chain oracles like Chainlink, which aggregate data from external sources and submit it to the blockchain. Delve into these oracle designs and their underlying rationale for a comprehensive understanding.

## Source
> Please provide related resource for the topics, including articles, research papers and more.

[A First Look into DeFi Oracles](https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=9566195)

[Toward Trustworthy DeFi Oracles: Past, Present, and Future](https://ieeexplore.ieee.org/stamp/stamp.jsp?arnumber=9785807)

## Others
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None