The beliefs of Islam are 7, and are referred to as "Emaan-Mufassal". These are:
- Belief in Allah
- Belief in His Angels
- Belief in His Books
- Belief in His Prophets
- Beleif in that everything that happens (good or bad) is by His will, alone.
- Belief in Life after Death
- Beleif in the Day of Judgement
Similarly, there are 2 Pillars of Islam:
- Shahaadah (Testimony)
- Salaah (Prayers)
- Zakaat (Charity)
- Sawm (Fasting)
- Hajj (Pilgrimage)
The Friday Prayer (Juma'ah) is relevant to the second belief listed above.
Hope that helps.