You might have heard of it. It's called Sharia. Although we tend to think of Sharia as a single set of laws that all Muslims follow, that's ridiculous. There are numerous competing ideas about Sharia, just as there are within any legal tradition. So people who embraced this worldview were called Muslims because they submitted to the will of God and they became part of the Ummah, or community of believers. This would be a good moment for an Uma Thurman joke, but sadly, she is no longer famous. I'm sorry if you're watching this, Uma Thurman.