Is Nano proof of stake?

Excuse me, could you please clarify something for me? I was reading about Nano cryptocurrency, and I came across the term "proof of stake." Now, I'm a bit confused as to whether Nano utilizes this consensus mechanism. Is Nano indeed a proof of stake cryptocurrency, or does it employ a different approach to achieve consensus and security on its network? I'd appreciate any insights you could provide to help me better understand the inner workings of Nano's blockchain.