The largest denomination in Islam is Sunni Islam, which makes up 75%–90% of all Muslims. Sunni
Muslims also go by the name Ahl as-Sunnah which means "people of the tradition [of
Muhammad]". These hadiths ("reports"), recounting Muhammads words, actions, and
personal characteristics, are preserved in traditions known as Al-Kutub Al-Sittah (six major books).
Sunnis believe that the first four caliphs were the rightful successors to Muhammad; since God did not
specify any particular leaders to succeed him and those leaders were elected. Sunnis believe that
anyone who is righteous and just could be a caliph but they have to act according to the Qur'an and the
Sunnah (Hadith), the example of Muhammad and give the people their rights.
Quran, Surat Al-Hujurat [49:13]: "O mankind, indeed I have created you from male and female and
made you peoples and tribes that you may know one another. Indeed, the most noble of you in the sight
of Allah is the most righteous of you. Indeed, Allah is Knowing and Acquainted."
Sunnis believe a caliph should be elected by the whole community.
The Sunnis approach God directly and there is no organized clerical hierarchy.
The Sunnis follow the Quran, then the Hadith. Then for legal matters not found in the Quran or the
Hadith, they follow four madh'habs (schools of thought): Hanafi, Hanbali, Maliki and Shafi'i, established
around the teachings of Abū Ḥanīfa, Ahmad bin Hanbal, Malik ibn Anas and al-Shafi'i respectively.
All four accept the validity of the others and a Muslim may choose any one that he or she finds
agreeable. The Salafi (also known as Ahl al-Hadith (Arabic: لهأ ث يدح لا; The people of hadith), or the
pejorative term Wahhabi by its adversaries) is an ultra-orthodox Islamic movement which takes the first
generation of Muslims as exemplary models.
The Shi'a constitute 10–20% of Islam and are its second-largest branch.
Shia Islam has several branches, the largest of which is the Twelvers, followed by Zaidis and Ismailis.
After the death of Imam Jafar al-Sadiq (the great grand son of Abu Bakr and Ali ibn Abi Talib) considered
the sixth Imam by the Shia's, the Ismailis started to follow his son Isma'il ibn Jafar and the Twelver Shia's
(Ithna Asheri) started to follow his other son Musa al-Kazim as their seventh Imam. The Zaydis follow
Zayd ibn Ali, the uncle of Imam Jafar al-Sadiq, as their fifth Imam.
While Sunnis believe that Muhammad did not appoint a successor and a caliph should be chosen by the
whole community, the Twelver Shias and the Ismaili Shias believe