Plain English
A Layer 2 is a separate blockchain that settles on top of a Layer 1 to scale capacity and cut fees. Arbitrum, Optimism, and Base are the major Ethereum Layer 2s.
How it actually works
Layer 2s process transactions off the main chain, batch the results, and post a compressed proof back to Layer 1 for final settlement. Users get near-instant confirmations and cents-per-transaction fees while still inheriting the security of the underlying chain. Withdrawing assets back to Layer 1 has a delay — typically a few minutes for ZK rollups, up to a week for optimistic rollups.
What it means for you
For most active DeFi use, members operate on Layer 2 rather than Ethereum mainnet. Lower fees, faster execution, same assets. The withdrawal delay matters for how you structure liquidity.
Our DeFi curriculum covers bridging to Layer 2, choosing between optimistic and ZK rollups, and managing settlement-finality trade-offs.
Educational content only. Not investment, tax, or legal advice.