Is Polkadot a Binance?

Could you please clarify for me if Polkadot is in any way related to Binance? I've been hearing about both these projects in the crypto space, but I'm a bit confused about their relationship. Are they competitors, partners, or are they completely unrelated? Also, if they are different, could you briefly explain the key differences between Polkadot and Binance? It would be really helpful for me to understand the nuances of these two projects.