Layer 2 (L2) blockchain
A Layer 2 (L2) blockchain is a secondary framework or protocol built atop an existing Layer 1 blockchain, aiming to enhance scalability and efficiency by offloading certain operations from the main chain.
In the EVM ecosystem, layer 2s build upon the existing infrastructure of the Ethereum network. Examples of popular Ethereum layer 2 blockchains include Optimism, Base, Apechain and Polygon.
There are a range of different layer 2 solutions, including rollups and state channels. These process transactions off-chain and periodically submit summaries to the Ethereum mainnet, reducing congestion and lowering fees.
This mechanism helps improve the performance and user experience of decentralized applications by enabling faster and more cost-effective transactions