Rasoolullah (SAW) said that the structure of Islaam is erected on five things, which are called the Arkaan (foundations or fundamentals). These five Arkaan are:

3. Belief in the Oneness of Allah and the Risaalat of Muhammad (SAW).

4. The five daily Fardh Salaat.

5. Zakaat.

6. Saum: Fasting in the month of Ramadan.

7. Hajj

These five fundamentals are also known as the Pillars of Islam. They are termed as such because of their great importance. It should not be understood that the obligatory acts of Islaam are confined to these five. There are numerous other obligatory acts, e.g. Jihaad in the Path of Allah, Commanding righteousness, Prohibiting evil, etc.