The Ethereum Support Layer: Optimism is a Layer 2 scaling solution for Ethereum that enables up to 2000 transactions per second (TPS). Specifically, it records batches of transactions submitted to the Ethereum main chain and runs them on a parallel Layer 2 chain using a process called transaction rollup. Simply put, this technique mitigates the majority of Ethereum's transaction computation and storage overhead. In a way, it's a solution that comes directly on top of Ethereum to supercharge the network. For Optimism, we can really talk about a layer that is superimposed on and dependent on the evolution of Ethereum. We could even talk about a "mother-daughter" relationship between Ethereum and Optimism, which share the same consensus algorithm and where the "daughter" chain lightens the load of the operations of the mother to which it is subordinate. Many of Ethereum's decentralized applications are on Optimism to provide a better experience for developers and users, both in terms of turnaround time and transaction fees.
Optimism has its own native token: OP allowing holders to get a vote related to upcoming updates to the protocol.