No, Optimism is not an ERC-20 token. Optimism is a Layer 2 scaling solution designed to enhance the scalability and performance of the Ethereum network. It utilizes Optimistic Rollup technology to process most transactions off-chain while leveraging the security of the Ethereum Mainnet. Optimism does not have its own native token; it is a protocol that works with the existing Ethereum ecosystem to improve transaction speed and reduce fees.