I think that every religion has different denominations and sects of spiritual inquiry. Islam is no different. The three main denominations of Islam of Sunni, Shi'a, and Sufi carry many similarities, but some points of divergence. Representing the largest cross section of followers of Isla, the Sunnis account for about 85% of all Muslims. One major point of disagreement between Shi'a and Sunni is about the role of leadership within the religion. Sunni Muslims believe in the spiritual sanctity and power of the Imam, while Shi'a Muslims largely believe that there are no spiritual rulers outside of the first four caliphs. This disagreement in leadership composes one specific differences between the majority branch and the secondary denomination that comprises about 10% of Muslim follwers. The Sufi branch of Islamic worship is the denomination that is the smallest of the three, emphasizing a spiritual and mystic connection to the religion. It is not as bound by dogmatic principles as the other two branches and seeks to obtain God by "emotional and intuitive faculties." I think that the Sufi branch probably poses the greatest amount of challenge to the dogmatic and singular conception of Islam and it is where the Sufis speak that those interesting in trying to broaden Islam should listen and pay attention.
Your question is technically incorrect as according to Islam there is no interpretation of the Koran and all Muslims are to strictly follow the Koran. The Koran is to be taken literally as the word of God and is not open to interpretation like the bible is. So, there is NO interpretation of Islam.
Having said that you should realize that there are 35,213 Qur'an verses, hadiths, Sharia laws and various Muslim scriptures commanding and encouraging killing, violence, war, annihilation, corporal punishment, hatred, boycott, humiliation, and subjugation aimed mainly against non-Muslims! Not quite the "religion of peace" that many people would like you to believe. Political correctness is dangerous especially when it comes to Islam.
The "Five Pillars" of Islam:
1- Profession of Faith, Shahadah, "There is no God but Allah, and Muhammad is his prophet".
2- "Prayer": "Five times a day"... "Fridays"... The "Salat":
3- "Give alms", "Zakat"
4- "Fasting", "Sawm", on the month of "Ramadan"
5- "Pilgrimage to Mecca", the "Hajj"
1-There is only "one God", Allah, creator of the whole universe, who is just, compassionate, and merciful. The absolute unity and power resides in God. Creator of life and death, the guide to righteous, the friend and protector of the sick and the poor. He chastises eternally the infidels to Hell, and he rewards the faithful with eternal Heaven.
-"Allah", "The God", comes from "Al" ("The"), and "Illah" ("God")... not just "a God", but "The God", for there is only one.
Believe in "Angels", who intercede with Allah for the forgiveness of the faithful.
2- "Muhammad", was the last of the great prophets. Jewish prophets and Jesus were his predecessors.
3- The "Koran", was the last of the sacred books, which include also the Torah, Psalms, and Gospels of Jesus.
4- "Life on Earth", is a test and only a preparation for the eternal life to come. the "faithful" are those who adore Allah, praise the Prophet Muhammad, obey the Koran doing good deeds, and fulfill the 5 pillars of Islam.
The Koran forbids representation of human and animal figures. It denounces usury, games of chance, alcohol, pork... "pride" is a cardinal sin.
5- The "Final Judgment": The faithful will go to eternal Heaven, and the infidels to eternal Hell, with the vividly rewards and punishments recorded in the Koran.
If it is meant Islam faith rules, they are:
- faith in the oneness of Allah (God, the one and only one God).
- faith in God Angels
- faith in all God holy books (including Torah, Psalm, Bible, and Quran)
- faith in all God prophets (including, among others, Noah, Abraham, Moses, Jesus, and Mohamed, peace upon them all)
- faith in in the Day of Judgment
- faith in destiny
If it is meant Islam pillars, they are:
- Witness that no God but Allah (the one and only one God) and prophet Mohamed is His Messenger
- Paying Zakat (specific compulsory Charity)
- Fasting Ramadan
- Pilgrimage for who can afford it
For other rules of Islam teachings, Islam morals, Islam and Quran Golden rules and for more information on the above, refer to the related attached questions listed below.