Loopring is an open protocol designed to build decentralized cryptocurrency exchanges, offering a robust layer-2 scaling solution on the Ethereum blockchain. It utilizes zkRollup technology to facilitate high-throughput, low-cost trading and payment features while maintaining Ethereum-level security. Loopring improves efficiency by processing transactions off-chain and only settling final states on-chain, thereby reducing gas fees and speeding up transaction times. The protocol aims to enable developers to create exchanges with better user experiences and reduced operational costs.