This article provides a comprehensive overview of Cross-Chain, which serves as a bridge connecting blockchain islands and facilitating the free flow of value and information, playing a crucial role in the Web3.0 era. The article delves into the origins, development, core characteristics, key technologies, and security aspects of cross-chain technology from multiple dimensions. It also looks forward to the future development trends, including the unification of standardized protocols, innovation in security and privacy protection technologies, and the construction of a multidimensional cross-chain service ecosystem. With the advancement of these technologies, cross-chain is expected to further promote the prosperity of decentralized applications, providing a secure, open, and efficient multi-chain world for users and developers, indicating the immense potential and bright future of blockchain technology in advancing global digital transformation.