Layer-2 Solution

What is Layer-2 solution? Blockchains currently suffer from scalability issues, and while decentralized and transparent, transactions are slow and costly. There are three existing scalability technologies, including the introduction of optimized blockchain protocols for each verification node, such as DAG, Hashgraph, Avalance, etc.; the immature sharding technology; and the Layer- 2 solutions.The public chain is by far the most effective way to achieve global consensus, but it is also the slowest database. Therefore, we should let the blockchain only carry things that are most suitable and good at such as decentralization. Other issues such as scalability and privacy can be solved through off-chain expansion solutions.Adding another layer on top of the blockchain, using the blockchain as an anchor, ensures security. Currently, some of the existing solutions are used to expand payments, some are used to expand smart contracts, and some are used for off-chain computi