How does Mina work?

Could you please elaborate on the functionality of Mina? I'm curious to understand how it operates and what makes it unique in the realm of cryptocurrencies. Could you break down its working principles and provide insights into its architecture and features? I'm also interested in knowing about its scalability, security measures, and the processes involved in transactions using Mina. Additionally, could you discuss any potential challenges or limitations associated with its operation? Thank you for your assistance in explaining this fascinating topic.