BOOK (Book Chain) is a decentralized reading and exchange system, an Ethereum sidechain that covers three core functionalities: content publishing, reading payments, copyright protection, and IP trading. It will achieve operational data recording, transparent allocation processes, and critical information on-chain in the aforementioned processes, creating a data ecosystem for project development and promoting more openness and transparency in project operations. Book Chain aims to incentivize readers to participate in building the reading community through the reward mechanisms of the cryptographic digital currency system and token-based payment for reading, truly realizing a "virtuous ecosystem" where readers can read for free and writers’ copyrights are protected, redefining book reading platforms with blockchain technology.