Is BNB BSC the same as BNB Smart Chain?

I'm curious, could you clarify for me if BNB BSC and BNB Smart Chain are in fact one and the same? As a cryptocurrency enthusiast, I've heard these terms used interchangeably but I'd like to ensure I have a clear understanding of their relationship. Are they referring to the same blockchain network, or do they have distinct functionalities or purposes? Your expertise in this area would be greatly appreciated.