the metaverse seamlessly integrates the real world with the virtual world and allows avatars to engage in a broad range of activities including entertainment, social networking, and trading. in this book, we dive into the metaverse by discussing how blockchains connect various metaverse components, digital currencies, and blockchain-empowered applications in the virtual world. on the other hand, web3 has also attracted considerable attention due to its uniquely decentralized characteristics. the digital economy, currently undergoing a rapid development, is a critical driver to highly efficient societies. it is imperative that we investigate how to use web3 technologies to address the critical concerns encountered during the development of the digital economy by fully exploring web3. in this book, we also share insights into the web3-based ecosystem in the metaverse; topics of interest include decentralized finance, digital assets, the asset-trading market, etc. unlikemost works on the subject, this book mainly concentrates on insights and discussions regarding blockchain, the metaverse and web3. in other words, it focuses on using blockchain technologies to enable an ecosystem for both the metaverse and web3. topics addressed include blockchain fundamentals, smart contracts, value circulation in the metaverse, the connection between the metaverse and web3, the establishment of the metaverse on the basis of blockchain technologies, decentralized autonomous organization, decentralized storage, digital economy, web3-based economic systems for the metaverse, etc. this book will be a valuable resource for students, researchers, engineers, and policymakers working in various areas related to blockchain, the metaverse and web3. we hope that it will also inspire readers from academia and industry alike, and ultimately help them create a truly open, fair, and rational ecosystem for the metaverse and web3.