Why does Islam often seem strange?

Islam may seem exotic or even extreme in the modern world. Perhaps this is because religion does not dominate everyday life in the West today, whereas Muslims have religion always uppermost in their minds, and make no division between secular and sacred. They believe that the Divine Law, the Shari'a, should be taken very seriously, which is why issues related to religion are still so important.

Do Islam and Christianity have different origins?

No. Together with Judaism, they go back to the prophet and patriarch Abraham, and their three prophets are directly descended from his sons, Muhammad from the elder son Ishmael, and Moses and Jesus from the younger son Isaac. Abraham established the settlement which today is the city of Makkah, and built the Ka'ba towards which all Muslims turn when they pray.