Although both Sunni and Shii Muslims accept and use the same Qur'an, believe in the same essentials of faith and practice the same five pillars of Islam, there are a number distinctive differences between Sunni and Shii orientations.

1) Leadership: Sunni Muslims accept the sequence of early rightly guided caliphs (Abu Bakr, Omar, Othman, Ali) while Shii Muslims insist that Ali, representing the family of the Prophet, should have been the first caliph after the Prophet followed by Ali's descendants. In Sunni orientation, the Caliph or the Imam (leader of Muslims) is elected among the Muslims based on his competence and leadership. Apart from the Prophet everyone is fallible. On the other hand, in Shii orientation, the Fourteen Pure and Perfect Ones (Ali, Fatima -Ali's wife and Prophet's daughter -their two sons Hasan and Husayn, and nine Imams) are all infallible. The Caliph should come from the descendants of the Prophet.

2) Sources of Law: While both Sunni and Shii accept the Qur'an and Sunnah of the Prophet as inspired authoritative textual sources, the Shii have maintained their own collections of the traditions that not only include the Sunnah of the Prophet but also those of Ali and the Imams. They regard the Imam as the supreme legal interpreter and authority. In his absence qualified religious scholars serve as his agents and interpreters of the law.

3) Religious Practices: Three important matters could be considered.

• Intercession: For Sunnis, God and human beings have a direct relationship. Learned scholars are not intermediaries but scholarly interpreters of the religion. Thus belief in saintly intermediaries are viewed as dangerous deviations. The only person who has intercession is the Prophet Muhammad whose intercession will be in the form of advocating on behalf of his followers on the Day of Judgement. For Shii, intercession is another avenue for salvation. Ali and the other Imams were divinely inspired models, guides and intermediaries between God and the believers.
• Holy Days and Celebrations: Along with those holy days that are celebrated by Shii and Sunni alike, Shii also mourn and celebrate the birthdays and death anniversaries of the Imams. Husayn's martyrdom at Karbala and the associated remembrance and ritual reanacment of the tragedy is a cornerstone of belief, personal and communal identity and piety. This incident accounts for the special character of Shii understanding of Islam as an oppressed community loyal to God and His Prophet's family.
• Ritual Practices: Sunni practice is centred on the five pillars of Islam and the associated practice of the Prophet. In addition to daily prayers, Shiism has developed dramatic recitations, passion plays and street processions centring on the tragedy of Karbala. These are believed to be expression of piety and regarded as earning spiritual merit.

We could conclude that Sunni orientation centres its practice around the Qur'an, the prophethood of Muhammad and his role as a person epitomising the ideal presented by the revelation of the Qur'an, hence God. Shii orientation on the other hand centres on the Qur'an, the personal aspects of the Prophet and loyalty to his family personified by Ali. While the Sunni orientation is the common denominator in the whole Muslim world, there are added beliefs and practices in the case of Shii orientation mainly introduced later by their deep love of the Prophet Muhammad and his family.