What makes Polkadot different?

Could you elaborate on what sets Polkadot apart from other cryptocurrencies? It seems to have generated quite a buzz in the blockchain community, but I'm curious to understand its unique selling points. Is it the interoperability feature that allows different blockchains to communicate with each other? Or is it something else entirely? I'd appreciate it if you could break down its key differences in a way that's easy to understand for a non-expert like me.