Blockchain is a decentralized distributed digital ledger that ensures the transparency and tamper-proof nature of transaction data while reducing the reliance on trust in centralized intermediaries. It achieves this by packaging transactions into "Blocks" in chronological order and utilizing cryptographic methods such as hash functions and consensus mechanisms to realize information that is immutable and traceable. In addition, blockchain supports programmable features such as smart contracts, providing a foundational basis for decentralized applications (DApps) and financial innovations. It is widely used in fields such as cryptocurrency and supply chain management.
1. Core Components and Data Structures
Block（Block）
Each Block typically consists of a block header (including the previous block hash, timestamp, nonce, etc.) and a block body (transaction list). The preceding and following blocks are linked by hashes to ensure the integrity of the Blockchain.
Hash and chain structure
The previous block hash in the block header links all blocks together; any tampering with packaged transactions will change the hash value, causing the chain to break and be rejected by the network nodes.
Merkle Tree and Patricia Merkle-Patricia Trie
Merkle tree is used for efficiently verifying whether transactions are included in a block, while Ethereum extends it to Patricia Merkle-Patricia Trie to optimize the storage and retrieval efficiency of state data.
2.Consensus Mechanism
Nodes in the Blockchain network need to pass through
Consensus Mechanism(Consensus Mechanism) to achieve consistency of the ledger state, common ones include Proof of Work (PoW) and Proof of Stake (PoS). The consensus mechanism not only determines who has the right to package new blocks, but also defends against malicious node attacks, ensuring the decentralization and security of the network.
3. Smart Contract
Smart Contracts are programs deployed on the Blockchain, characterized by automatic execution, immutability, and self-verification, capable of automatically completing agreed operations when specific conditions are met.
They run in environments such as the Ethereum Virtual Machine (EVM) and can enable various innovative applications like decentralized trading and trustless financial tools (DeFi) (Ethereum).
4. Security and Decentralization
The security of the Blockchain is based on
Cryptographic Hash 、
Digital Signature and
Distributed Storage The mechanism makes it almost impossible for single-point tampering or forgery to occur. At the same time, the network nodes jointly maintain the ledger without the need for a centralized institution, reducing the risks of censorship and downtime, and achieving high availability and censorship resistance.
5. The application of Blockchain in the cryptocurrency industry
- Digital Currency Bitcoin, Ethereum and other blockchain-based native assets have become vehicles for value storage and exchange.
- Decentralized Finance (DeFi) Financial innovations such as lending, automated market making (AMM), and derivatives trading are rapidly developing on the Blockchain.
- Cross-Chain Bridges : Achieving asset interoperability between different public blockchains, such as solutions for bridging Ethereum to other networks.
- NFT and Metaverse A digital asset certificate with a unique identifier, providing a new model for the trading of art, games, and virtual assets.
