how many main muslim groups are there?

Answer 1

Way too many. Each major group is further broken into factions. Each one of these could have splinters off of them, dependent upon whether some "new" leader comes along.They don't even get along with each other.

Answer 2

Islam is one, therefore the followers - One who submits his will to GOD should also be One.

But the mainstream of Islam has been divided into many groups.

Basically the Sunni and the Shia...

the Shia give much importance to the relatives of the Prophet Muhammed (Peace Be Upon Him) and forget the fundamentals.

The Sunnis follow the rulings and give the required importance.

There have been other groups that have actually nothing to do with Islam as they have deviated from the mainstrram of islamic Monotheism and 'seal of the Prophethood' (Muhammed)...

So if at all you want to know about Authentic Islam, read the Quran from authentic sources with translation and the authentic Hadeeth (Sayings of the Prophet that are second part of divine revelation). But make sure to read the context and background of the Quranic verses and the Hadeeth.

Peace Be With You.

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