Islam

Dates
610-632 Muhammad (PBUH)
632-661 Rashidun (first four Caliphs)
632-634 Abu Bakr
634-644 Umar ibn al-Khattab
644-656 Uthman ibn Affan
656-661 Ali ibn Abi Talib
661-750 Umayyad Dynasty
750-935 Abbasid Dynasty
935-1517 Regional Leadership
1517-1917 Ottoman Empire

Pillars
1. Shahadah (faith)
2. Salat (prayer)
3. Zakat (almsgiving)
4. Sawn (fasting)
5. Hajj (pilgrimage)
Possible 6th: Jihad (struggle)

Sunni vs. Shia
In very basic terms, the difference between Sunni and Shia Muslims is their disagreement about when the last of the Rashidun Caliphs, Ali ibn Abi Talib, should have ruled. While Sunnis (seen in light green on the map to the right) believe that Ali was rightfully the fourth of the Rashidun, the Shia (shown as the dark green on the map opposite, primarily found in Iran) believe that Ali ibn Abi Talib should have been the first Caliph, and from that point on the Caliphate should've been passed down through the rest of Muhammad's (PBUH) blood stream (next, daughter Fatima).