What are Rollups?
Rollups are like express lanes for Ethereum. They batch tons of transactions, compress the data, and post a summary to the Ethereum mainnet. That way, you get lower gas fees and faster transactions — without sacrificing security.

There are 2 main types:
• ZK Rollups – use zero-knowledge proofs to validate transactions instantly. Fast and efficient.
• Optimistic Rollups – assume transactions are valid unless challenged. Slower finality, but simpler to build.

Why care?
Rollups are how Ethereum scales to millions of users. Projects like Arbitrum, Optimism, and zkSync are all building the future of L2. If you’re using any of them, congrats — you’re already on the fast lane.