Arbitrum One

Arbitrum One is a Layer 2 (L2) optimistic rollup chain that implements the Arbitrum Rollup protocol and settles to Ethereum's Layer 1 (L1) chain. It lets you build high-performance Ethereum dApps with low transaction costs and Ethereum-grade security guarantees, introducing no additional trust assumptions. This is made possible by the Nitro technology stack, a "Geth-at-the-core" architecture that gives Arbitrum One (and Nova) advanced calldata compression, separate contexts for common execution and fault proving, Ethereum L1 gas compatibility, and more.