The 3 main religious groups are: -Christianity -Judaism (Jewish) -Islamic The previous answer is not correct. The religions listed above are the Abrahamic Religions and not the main religious groups of the world. There are literally hundreds of thousands of religious groups, and possibly thousands of "main" religious groups.
Christianity and Islam
Reform (Least Religious) Conservative (More Religious) Orthodox (Most Religious)
Sunnis and Shiites
yeast and moulds
what are the main mountains in Cuba
Roman catholics and church of England protestants.
islam, chistianity, judaism
I think they are the Shia Sunni and Kurds or possibly Sufi
The Religious and the Philosophical; the names are pretty good descriptions of what they're about.
cuba
Groups as in bands = Metallica and iron maiden Groups as in genre = death metal and black metal