What is Layer-2 Scaling Solution?

Layer-2 scaling solutions are protocols that integrate into blockchains like Bitcoin and Ethereum as separate, secondary layers built to increase transaction throughput and reduce transaction costs. These Layer-2 solutions use technologies such as sidechains, state channels, Zero-Knowledge Rollups (zk-Rollups), and a variety of other Layer-2 solutions. Examples of Layer-2 solutions include Lightning Network (for Bitcoin), SKALE Network (for Ethereum), and Arpa Chain (blockchain agnostic).