DIVISIONS IN QUR'AN

Muslims as a whole accept the Qur'an as divine revelation, revealed as verbal inspiration to Nabie Muhammad (SAW) over the twenty three year period of his  Nubuwwah.   He received revelation  a few verses (Ayaat) at a time or sometimes as an entire Surah and then oversaw the compilation of Ayaat; placed in an inspired order to form a chronology even though Ayaat may not have been received in chronological order, to form the complete Qur'an.

For example, the very first revealed Ayaat of Surah Alaq, are placed in the last Juz, and other early revealed Ayaat from Surahs Muzzammil & Al-Muddathir are  placed in the second last Juz; whereas Surah Fatihah which was revealed as a complete Surah in and around the time of Hjira;  is placed at and as the opening verses of Qur'an. 

The Qur'an is a substantial document that internally refers to itself as al Tanzil (The Revelation); al Huda (The Guide); al Haqq (The Truth); al Tadhkira (Admonishment); al Amr (The Commandment); al Furqan (The Criterion (of right and wrong)); al Mau'izah (The Admonition); al Rahmat (The Mercy); al Burhan (The Argument); as-Sirat al-Mustaqim (Straight Path); Ahsan al-Hadith (The Fairest of Statements); Kalam Allah (Word of God); and several other. 

As such the Holy Qur'an is the liturgical scriptures of the Muslims;  each and every Muslim aught to have a relationship with it, that moves him or her to you tears whenever they read it.  In fact every Muslim has a personal duty and responsibility to devote themselves to daily reading the Qur'an, understanding it verse, and  daily ponderances  and aught to memorize it in its original Arabic because it is the rope that connects us to Allah (SWT). 

30 Juz - Qur'an divisions

Arabic is the God chosen language for the Qur'an and it lays down the law and commandments, codes for social and moral behaviour, contains comprehensive religious philosophy and narratives from the start of creation to the epics of the prophets, to resurrection of the soul and beyond. The Qur'an is divided into 114 Surahs (chapters),  consecutively numbered from 1-114  Surahs, each of varying length.  But its collective Ayaat (text) is also divided into thirty (30)equal sections of  more-or-less equal length, each referred to as a Juz in Arabic, a "para" in Persian (Farsi), a "Sipara" in Urdu, and a "paroo" in South Asian-IndoPak region.

These thirty (30) divisions are purely to facilitate recitation of the entire Qur'an over a period of one month or 30 days. The sections makes it an easy reference system for those who wish to complete (Khatam)  a reading of Qur'an over 30 days. However the Qur'an is also divided into seven equal parts, each  called a Manzil, for those who wish to complete an entire recitation of Qur'an over  7 days.  It is highly recommended that Muslims complete a reading of the Qur'an at least once every year at the individual level. 

Furthermore each  Juz / Para / Sipara is sub divided into two parts, each called a Hizb (ahzab  pl.) which is half the length of a Juz. Meaning there is a total of 60 Hizb in the Qur'an. Each Hizb is divided into four groups, each referred as a Maqra. These are marked  as Hizb Ar-rub' (meaning 1/4, first quater), Hisb An-nisf (meaning 1/2, half), and Hizb Ath-thalata (meaning 3/4, three quarters) in the margin, in Arabic, of the relevant pages. 

Restated a Maqra is one-eight of a Juz. Then there are further divisions according to subjects called "Ruku" which can span both a Surah or a Juz, (see table below - Surah column) because its a division marker and not a physical division.  At the lowest level, the Qur'an consists of numbered individual Ayah (sing.) which can roughly equates to a verse but an Ayah can sometimes span two, three, or more sentences. An Ayah is normally determined by its rhythm and cadence in the Arabic tongue. In toto there are there are 6,327 Ayaat in the entire Qur'an, but amounts to 6348 when the Basmillah at the beginning of each Surah are included.

The way the Qur'an is divided into these easily readable portions are somewhat different for those  copies of Qur'an printed in the Arab world and for those printed in South Asian-IndoPak. Qur'ans printed in the Arab world do not include "Ruku" markings and those printed  in South Asia do not include Hizb markings. Whichever Qur'an is used for memorization purposes, is purely a matter of choice, which is also extended to either  a 13 line or a 15 line Qur'an. 

But regardless of divisions, whether by Surah, Juz, Hisb,  Maqrah, Ruku, Ayaat or Ayah,  each and every Qur'an printed throughout the Muslim world are word-for-word identical to one another. So  whichever division  (part) you wish to adopt to either read or memorize  of the Qur'an is entirely up to you. What I can add, is that memorizing the Qur'an can take anything from 2 to 10 years subject to the level of your personal  commitment.

One consolation is that currently there hundreds of thousands, if not millions  of Hufaadth — a person who committed the entire Qur'an to memory  who can recall any and every verse at random — globally. If all of these people could achieve it, it's definitely attainable and within your or my reach.  Allah Wa alam! (Allah Subhanahu wa Ta'aala  knows best).