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Layer 2
Ethereum•blog.difficulty.intermediate
Layer 2 (L2) refers to scaling solutions built on top of a blockchain (Layer 1) to increase transaction speed and reduce costs.
Simple Explanation
Imagine a busy highway (Ethereum) with traffic jams. Layer 2 is like building express lanes above the highway where most traffic moves faster and cheaper, while still being connected to and secured by the main highway.
How It Works
- Transactions happen on Layer 2 (off the main chain)
- Transactions are bundled together
- Bundles are posted to Layer 1 for security
- You get speed and low cost of L2 + security of L1
Popular Layer 2 Solutions
- Optimistic Rollups: Arbitrum, Optimism
- ZK Rollups: zkSync, StarkNet
- Sidechains: Polygon
- State Channels: Lightning Network (Bitcoin)
Benefits
- Lower Fees: Transactions cost cents instead of dollars
- Faster: Transactions confirm in seconds
- Scalable: Can handle many more transactions
- Secure: Inherit security from Layer 1