For the great importance attached to the ‘Surat al-Fatiha’ (The Opening), it is also known as ‘Ummul Qur’an’ and ‘Ummul Kitab’ meaning the ‘Mother of Qur’an’ and ‘Mother of the Book’ respectively. This chapter, based on a popular opinion is believed to be the first completed chapter of the Qur’an revealed to the Holy prophet (PBUH).
Meanwhile, the chapter, in comparison with other chapters of the Qur’an regarding its tone and melody, has a particular style, which is clearly different and extraordinary.
In the sense that other chapters contain instructions from Allah but, in this chapter, His words are uttered on behalf of the servants. In other words, in ‘Surat al-Fatiha’, Allah has taught His servants how to supplicate and speak to Him, simply and without a mediator.
Besides, it is believed that the chapter apart from referring to the Resurrection, it also presents facts concerning the Unity of the Divine Essence, Unity of Attributes, Unity of Divine Acts, and Unity of Worship. Therefore, the chapter is indeed the essence of the whole meaning of the Qur’an.
In addition, the following saying of Amir al-Mu’mineen Ali (AS) summarizes and shed more lights on the significance of Surat al-Fatiha:
“All secrets of Allah are in Divine Books; and the contents of all those Divine Books are comprised in the Qur’an; and what is found in the Qur’an is condensed in Surah Al-Al-Fatihah, and what is in Al-Fatihah is gathered in / bismillah /, and what is in /bismillah / is concentrated in / b /, (the first letter of ‘Bism-il-la ‘ )…” 
 Makhzan al-’Irfan, Vol. 1, P. 28; Masabih al-Anwar, Vol. 1, P. 435.