How does FMCPAY work?

Could you please explain in detail how FMCPAY operates? I'm curious about the technology behind it, the user experience, and how it differs from other payment systems. Specifically, how does it facilitate secure and efficient transactions for both buyers and sellers? Additionally, how does FMCPAY integrate with traditional financial systems and cryptocurrencies? Is there a specific use case or scenario where FMCPAY excels over other solutions?