[MandieD]

Thank you for that! The only major division I was aware of among Muslims was Sunni and Shia, but I guess that's a bit like someone being startled by cultural and religious differences between Roman Catholics and Protestants - they all acknowledged the same religious authorities until about 1500 or so, have the same holy book and their worship services are pretty similar (there are more differences among Protestants than there are between some of the Protestants' and the Roman Catholics' services)