Shia
The Sunnis belong to Islam and Shiites are a false sect who claim to be part of Islam.
Nation of Islam
I believe that the majority of Iranians are Shi'a Muslims.
They are Muslims. It is irrelevant to think about which sect they belong to. No sects in Islam with same meaning as in Christianity. The sects in Islam are more or less different schools or different groups that differ only on minor historical issues.
Sufism is a branch of the Sunni sect of Islam. Sunni's are the most popular sect.
Of Islam.
No
Sunni
Sunni sect is the largest sect of Islam. Shia are in very less number. Sufi is not a sect. It is a way of life for some of the Muslims who seek pleasure of Almighty Allah by excessive prayer and devotion.
sadducess
The Kurds belong to many different sects, most notably being the Sunni sect as the majority. There is also a the Shia sect from among Kurds, most from the Shia sect live in Iran and Iraq.