Answer: They are fourteen pillars, which are:

1. Standing in the obligatory prayer for the one who is capable

2. The opening Takbīr, which is saying: "Allāhu Akbar" (Allah is the Greatest)

3. Reciting Surat al-Fātihah

4. Rukū‘ (bowing) while straightening one’s back and making his head in alignment with his back

5. Rising from Rukū‘

6. Standing up straight

7. Sujūd (prostration): It is by placing one’s forehead, nose, palms, knees, and tiptoes on the ground while prostrating

8. Rising from Sujūd

9. Sitting between the two prostrations

It is an act of Sunnah to sit on one’s left foot, while keeping the right foot straight upward and keeping its toes facing the Qiblah.

10. Serenity, which is calmness in performing each physical pillar

11. The last Tashahhud

12. Sitting for Tashahhud

13. Making Taslīm by saying: "As-salāmu ‘alaykum wa rahmatullāh" (may the peace and mercy of Allah be upon you) - twice.

14. Maintaining the prescribed order of the pillars as mentioned; so, if one intentionally prostrates before bowing, his prayer is invalid. However, if he does so unintentionally, he must return back to perform bowing first then prostrate.