layer3

What are rollups?

Rollups are a Layer 2 scaling solution for blockchains (like Ethereum) that bundle or "roll up" multiple transactions into a single batch, then process them off-chain while ensuring security on-chain. This reduces the workload on the main blockchain, improving scalability.

There are two main types of rollups:

Optimistic Rollups:

Assume transactions are valid by default and only run computations off-chain.
Disputes are resolved by posting fraud proofs on-chain if someone challenges a transaction.
Example: Arbitrum, Optimism.
ZK-Rollups (Zero-Knowledge Rollups):

Use zero-knowledge proofs to prove off-chain transaction validity to the main chain without the need to reveal transaction details.
They are more efficient but more complex to implement.
Example: zkSync, StarkWare.
Rollups reduce gas fees, increase transaction speed, and help scale blockchains while inheriting security from Layer 1.