What is the most popular BCD code?

Could you possibly enlighten me on a subject that's been piquing my curiosity? I've been hearing quite a bit about BCD codes lately, and I'm wondering, what exactly is the most popular BCD code? I've been trying to wrap my head around this, but it seems like there's quite a variety of them. Is there a specific one that stands out as the most widely used or recognized? I'd really appreciate it if you could break it down for me in a way that's easy to understand. Thanks in advance for your help!