Is Metis an Ethereum?

Could you please clarify whether Metis is an Ethereum-based platform or a separate cryptocurrency? I've heard some confusion surrounding this matter, and it seems important to differentiate between the two. Ethereum is a decentralized, open-source blockchain platform that enables smart contracts and decentralized applications, while Metis appears to be a project aiming to solve scalability and interoperability issues. However, I'm not entirely sure if Metis is built on the Ethereum blockchain or if it's an independent network. Could you elaborate on the relationship between Metis and Ethereum, if any? Thank you.