How do we use a bit?

Could you elaborate on how exactly we utilize a "bit" in the context of cryptocurrency and finance? Is it simply a unit of measurement, akin to a penny or a cent in traditional finance? Or does it hold a more nuanced and complex role within the blockchain ecosystem? I'm particularly interested in understanding how the concept of a bit ties into transactions, data storage, and the overall security and functionality of decentralized networks. Can you provide some real-world examples or scenarios to help clarify your explanation?