On-chain data is a true reflection of the blockchain ecosystem, recording every transaction, address interaction, and smart contract dynamics, characterized by openness, transparency, and immutability. By analyzing on-chain data, one can precisely capture the flow of funds, user behavior, and network health, such as tracking whale movements, identifying market sentiment, and assessing project risks. Technical methods include address clustering, transaction graphs, Gas fee fluctuations, and on-chain derived indicators (such as NUPL, MVRV), providing data support for optimizing DeFi strategies, regulatory compliance, and investment decisions. As analytical tools evolve, on-chain data is becoming a core intelligence source in the Web3 era.