Sidechain is a separate blockchain that is created for scalability of the main network and is connected to it by a two-way bridge for making transactions.

“[The use of sidechains] provides users with access to innovative cryptocurrency systems. They [the systems] can more easily interact with each other and with Bitcoin, avoiding liquidity shortages or market fluctuations that are associated with [the emergence of] new assets.”

Advantages:
✔️ Increases the throughput of the main network;
✔️ The flexibility of sidechains allows developers to experiment with the technology without compromising the security and reliability of the blockchain;
✔️ The functionality of main networks is expanding through sidechains.
Thanks to the latter, project teams can create and test dApps that are not supported by the parent blockchain.
testing new developments on the sidechain involves lower financial costs, which is due to lower network congestion.

💬 Sidechains are one of the convenient options for scaling the blockchain, which also reduces user costs for transactions.