Any Muslim women out there?

Hi guys! I’m raised a Christian and I was thinking today about how in history classes you always learn in detail about different denominations of Christianity, but, at least where I’m from, you don’t really learn about Islam. I was just wondering if someone could explain the different sects of Islam, what you believe in, why some women wear a hijab, etc. If this was offensive in any way, I’m so sorry! I would just really like to learn more about other cultures and religions different from my own. Thank you!