The major beliefs of Islam can be summed up in the Five Pillars.
1: There is no God but Allah and Muhammad is His Prophet (Shahadah)
2: Prayer five times a day. (Salah)
3:The Giving of Alms. (Zakah)
4: Fasting during Ramadan (Sawm)
5: Making the pilgrimage to Mecca (Hajj)
In addition to these practices, Shi'a Muslims often add three additional practices which they consider essential to the religion of Islam.
The first is jihad, which is also important to the Sunni, but not considered a pillar. The Most important Jihad is defined as the 'struggle with the self.' With others being;
The Jihad of the tongue,
The Jihad of the hand,
and the Jihad of the sword.
The second is called Amr-Bil-Ma'rūf, or "Enjoining to Do Good", and it asks every Muslim to live a virtuous life and to encourage others to do the same.
The third is Nahi-Anil-Munkar, which is the "Exhortation to Desist from Evil", this asks Muslims to refrain from vice and from evil actions and to encourage others to do the same.
The major beliefs of Islam are the following:
1: Islam is Monotheistic, that is, it believes in only ONE God. God (whose name in Arabic is Allah) is not a trinity in Muslim belief.
2: Allah sends Prophets to guide humankind. There have been many prophets one of whom was Jesus and another of whom was Muhammad. Muhammad is also God's last prophet in Islamic belief.
3: The Qur'an is Allah's inerrant, infallible scripture (ONLY in the Arabic.) All translations in other tongues are both capable of error and fallibility. The Qur'an was brought to Muhammad by the Angel Gabriel.
4: Everyone will be brought to the day of Judgement by Allah and assigned a place in either heaven or hell.