The sects and divisions of Islam
Islam is one of the three main monotheistic religions that believe in the same God, Abraham's God. So there are several similarities between Judaism, Christianity, and Islam; and all three religions believe in the same God, and believe that God is the Creator of mankind and all other things in the universe. The followers of Islam, i.e. the Muslims even recognize Jesus, although only as a less important prophet. Two other prophets from the Old Testament, Moses and Abraham are much more important in the Islamic religion. But the most important prophet is Muhammad, who lived from year 570 to 632.
When did Islam begin? During the years 610 to 632 Muhammad wrote down the Koran, but according to Muslims, then it would be wrong to call him the author, because they believe that the words of God, Allah, were dictated to Muhammad by the Archangel Gabriel.
It would also be wrong to call Muhammad the founder of a new religion, Islam. The way the Muslims explain the beginning of Islam and the origin of the Koran is that God's words in the Koran are bringing the religion back to its original uncorrupted faith of Abraham.
The Koran and other Holy Scripts of Islam were written down in Arabic, and Muslims do not recognize any translated versions into other languages as holy. Only the original Arabic version that contains God's exact words are fully accepted.
The Koran has a very complete set of rules of how to live in a daily life; how to behave in the private sphere and how to behave in public (and even Non-Muslims might be impressed over the details and completeness of how to live in a daily life).
Again the Islamic fundamentalists maintain that the words in the original scripts (now 1,400 years old) are given by God, and thus perfect. The fundamentalists see no reason to translate the scripts, nor do they see any reason to modify or interpret and implement the rules of how to live into a modernized world. And the most extreme see no reason for the secular state or government to make any laws, because all is already defined in the Koran.
The most important issue to bear in mind when evaluating Islamic laws is that for the Muslims there is not anything to be found which can be compared the Christian tradition of the 'two keys' or 'two swords', i.e. there is only one set of rules and not any matters of the church and matters of the state.
Also the Koran and the Sharia set up rules for what to do and what not to do in all aspects of life, and it has detailed descriptions of how to punish crimes and violations of the rules given by God.
Different Denominations and Sects
There are several different denominations and sects within Islam. The two most important are the Sunni Muslims and the Shia Muslims. And there are different traditions and interpretations of beliefs between the different sects, just as there are different traditions in the Middle East as compared to traditions of the Muslims in Africa and the Far East Asia. But there is one thing which is common for all Muslims. All Muslims have the fundamental 5 pillars in common.
The Five Pillars
The Five Pillars of Islam are the basics of Islam and the ideal goal for any Muslim is to act up to all five, but the only dogmatic pillar is the first and most important.
The first pillar is: The Shahadah, the confession of all Muslim's faith: There is only one God, and Muhammad is his Prophet.
The second pillar is: The Salah, the ritual prayer made five times each day. The Salah is performed with the face towards the holy Kaaba in Mecca.
The third pillar is: The Sawm. The yearly one month's fasting during the Ramadan. During the Ramadan the Muslims must not eat or drink from dawn to dusk, and they should during the day reflect over how to live a life without any sins.
The fourth pillar is: The Zakat. The Muslim's way of charity, to give alms. This giving cannot be compared to a voluntary charity, instead it is a religious obligation. Strictly speaking then the giver of the alms does not give money to the receiver, but the Zakat is given to God, and the one who receives the alms should only be thankful to God.
The fifth pillar is: The Hajj, the pilgrimage to the holy city of Mecca. All Muslims who can afford it are supposed to make this pilgrimage once in their lifetime. After the the Hajj pilgrimage then the person is called a Hajji, this tittle gives prestige, however, the pilgrimage should not be performed to get a higher social status, but the Hajj should only be made in honor of God.
Ref: The divisions of Islam, illustrating the different sects of Islam