What is the difference between BNB and BSC?

Could you please explain the key distinctions between BNB and BSC? I'm particularly interested in understanding how these two entities differ in terms of their functionality, usage, and their roles within the cryptocurrency and blockchain ecosystem. Also, it would be helpful if you could elaborate on the advantages and disadvantages of each, as well as any potential synergies or areas where they might overlap. Thank you for clarifying this for me.