Sunni Islam represents

Main group in Islam, making up 90% of the religion's adherents. Has been dominating almost continuously since 661, when the Shi'is departed from the main fold (the Kharijis left in 658). Sunni Islam claims to be the continuation of the Islam as it was defined through the revelations given to Muhammad and his life, a claim which is substantiated through the fact that Shi'i Islam for a number of decades had very little following and had no real, formal organization. As for the theology, Sunni Islam represents no more of a continuation of Islam than the other orientations.
Hence one should be careful about thinking of Sunni Islam as mainstream Islam, and clearly refrain from calling it "orthodox". None of the 3 orientations of Islam coming out of the schisms of the 7th century, can do no less than trace their origins back to the very first Muslim societies, and for the bystander none of the orientations must be deemed as inferior to the others.
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