What is a Rollup?
A rollup is a Layer 2 scaling solution that executes transactions off-chain but posts transaction data to the main chain, inheriting its security.
Rollup Types
- Optimistic: Assumes validity, allows challenges (Arbitrum, Optimism)
- ZK (Zero Knowledge): Proves validity cryptographically (zkSync, StarkNet)
Benefits
- Much lower fees than L1
- High throughput
- Ethereum-level security