Sura means a "chapter" of the Qur'an. There are 114 suras, and Muslims generally refer to them by the name given to each one, rather than by number. Aya means literally a "sign", and so a part of the Qur'an, generally one verse. Estimates differ, but there are commonly said to be 6,247 verses, 77,934 words and 323,621 letters in the Qur'an. To give an idea of its length, the Qur'an is a little shorter than the New Testament. For recitation the Qur'an is divided into 60 sections, known as "hizb", which do not correspond at all with the chapter divisions.

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