Blockchain Technology Explained

Core Concept - Blockchain technology is a distributed digital ledger that provides an unchangeable, transparent, and decentralized record of transactions, enabling systems that do not require trust in a central authority [1] Group 1: The Problem Blockchain Solves - The double-spend problem in digital currencies arises from the ability to create infinite copies of digital assets, necessitating a central intermediary like banks to prevent fraud [4][5] - Satoshi Nakamoto's creation of Bitcoin introduced blockchain as a solution to the double-spend problem, allowing a network of disconnected individuals to agree on a shared transaction history [6] Group 2: How Blockchain Works - Transactions are recorded in blocks, which are linked together to form a chain, with each block containing transaction data, a timestamp, and a reference to the previous block [7] - Cryptographic hashing ensures data integrity, as even minor changes to input data result in a completely different hash, making tampering evident [8][9] - The immutability of blockchain is achieved through cryptographic links between blocks, making it nearly impossible to alter past transactions without detection [10][11] Group 3: Consensus Mechanisms - Consensus mechanisms are rules that participants follow to validate transactions and add new blocks to the blockchain [12][13] Group 4: Core Properties of Blockchain - Key properties include decentralization, immutability, transparency, and security, which distinguish blockchain from traditional databases [14][17] - Public blockchains are open and permissionless, while private blockchains are controlled by a single organization, and consortium blockchains are managed by a pre-selected group [15][16] Group 5: Applications Beyond Cryptocurrency - Smart contracts, introduced by Ethereum, enable self-executing agreements that are transparent and immutable, unlocking various applications such as decentralized finance, supply chain management, and digital identity [16][19] Group 6: Challenges Facing Blockchain Technology - The blockchain trilemma highlights the difficulty of achieving decentralization, security, and scalability simultaneously [18] - User experience remains a barrier for mainstream adoption, and energy consumption of Proof of Work models raises environmental concerns [18]