Optimism (OP) is a layer-two blockchain on top of Ethereum. Optimism benefits from the security of the Ethereum mainnet and helps scale the Ethereum ecosystem by using optimistic rollups. That means transactions are trustlessly recorded on Optimism but ultimately secured on Ethereum.
Optimism is one of the biggest scaling solutions for Ethereum with over $300 million in TVL. It is home to 35 protocols, the biggest being Synthetix (SNX), a derivatives exchange, Uniswap (UNI), a DEX, and Velodrome (VELO), an AMM. Users can begin their journey on Optimism by adding the chain on their Metamask and bridging tokens like ETH to the L2