The book does a great job outlining how Islam changed from Muhammed's original vison to the modern day, and interestingly points out how world events around the Middle East such as the Mongols in the 13th century and the Crusades in the 11th century shaped the religion and its followers.
I think it‘s a good idea to read up on something you don't understand. I learned more about Islam in these 191 pages than I had in my prior 55 years.