Is Avalanche built on Ethereum?

I'm curious about Avalanche's technological foundation. Could you clarify whether Avalanche is indeed constructed on the Ethereum platform? This question seems to hold significant importance in understanding the infrastructure and functionalities of Avalanche. If it's built on Ethereum, then that would mean Avalanche inherits certain characteristics and capabilities associated with the Ethereum ecosystem. Conversely, if it's not, then Avalanche must have its own unique technological underpinnings. It would be enlightening to gain insights into this matter. Could you please shed some light on this aspect?