Is cosmos built on Ethereum?

I've been hearing a lot about Cosmos lately, and I'm trying to understand its technological foundation. Could you please clarify if Cosmos is built on Ethereum? I'm curious to know if they share a common blockchain infrastructure or if they are completely separate entities. It seems like both platforms have gained significant attention in the crypto space, so I'm eager to learn more about their relationship, if any. Thank you for your time and assistance in clarifying this matter.