HC coin, fully known as HyperCash in English and Super Cash in Chinese, is a new decentralized, open source, cross-system digital cryptocurrency that is the connecting point of all blockchain systems, allowing the free exchange of value and information between different blockchain systems. HC coin has dual side chains and is compatible with both blockchain and DAG distributed systems. It is developed based on a stable blockchain system based on the UTXO model to establish connections between blockchain-based and non-block-based systems to achieve information interconnection between different blockchains.< P class=" P1 ">HC chain fully realizes anti-quantum characteristics and privacy protection, supports the mixed consensus of PoW+PoS, focuses on the in-depth research and development of the underlying technology of blockchain, and provides HyperExchange with the value token needed to maintain the stability of the system. At the same time, HCASH will upgrade all the proposed technical features of HC: anti-ASIC, INTELLIGENT lightning network Protocol HAILP (HCASH AI Lighting Protocol) and smart contract have been listed in the next development plan. HyperCash, together with HyperExchange, will provide HCASH with a solution for inter-blockchain value connectivity, and on this basis, realize the free flow of information and value between blockchain and non-blockchain distributed ledgers (such as DAG), laying the foundation for the construction of multi-asset distributed business application ecosystem.