RollApps (short for "rollup applications") are a layer-2 scaling solution primarily associated with blockchain technology, designed to improve transaction throughput, reduce costs, and maintain security by leveraging the underlying blockchain (layer 1). They achieve scalability by processing transactions off-chain and only submitting compressed proofs or data back to the main chain.

1. Optimistic Rollups
How they work: They assume transactions are valid by default and only verify them if challenged. Participants can submit a "fraud proof" if they detect incorrect computations.

2. ZK Rollups (Zero-Knowledge Rollups)
How they work: They use cryptographic proofs (zero-knowledge proofs) to verify transactions off-chain and submit validity proofs to the main chain.

Key Benefits of RollApps:
Scalability: Significantly increase the number of transactions per second (TPS) compared to the main blockchain.
Lower Fees: By processing transactions off-chain, users pay less in gas fees.