Rollups (Optimistic, ZK‑Rollup)
Also known as: Layer‑2 Rollups, Optimistic Rollups, ZK Rollups
Scaling solutions that batch transactions off-chain and submit proofs or fraud proofs on-chain.
Rollups are Layer‑2 solutions that aggregate multiple transactions into a single batch, executing them off-chain and then posting a summary to the main chain. Optimistic Rollups assume transactions are valid and rely on a dispute/fraud proof window; ZK‑Rollups submit zero‑knowledge proofs for immediate verification. Both reduce gas costs and increase throughput while inheriting security from Layer‑1. They power many Ethereum scaling networks and support smart contracts, token transfers, and DeFi use cases.