The Qur'an or Koran is the primary holy text of the Islamic religion. The Qur'an is heavily criticized, especially in the West, for its consideration of women as inferior to men, its advocacy of intolerance towards non-Muslims, and its extremely violent system of punishment for crimes (especially victimless "crimes" such as extramarital sex, homosexuality, blasphemy and apostasy).
Apart from the Qur'an, the vast majority of Muslims also consider haddith literature, the traditional teachings and sayings of Muhammad, as secondary religious scripture.
According to Islamic doctrine, the Qur'an was dictated by God to Muhammad in Classical Arabic through the angel Gabriel. However, the Qur'an did not exist in a complete form before Muhammad's death in 632 CE (it was largely recorded and transmitted by memory!). There is evidence of a competing version. There is textual variation in manuscripts. There are no early manuscripts, suggesting they did not exist. The Qur'an evolved over the hundred years after Muhammad's death. The Qur'an contains internal contradictions and weaknesses.     
- "It is now evident that the position held by orthodox Muslims concerning the origin of the Qur'an is simply untenable in light of the clear evidence. The view echoed by Ahmad Von Denffer that what is in the Qur'an today is an exact duplicate of the God's tablets in heaven-transmitted to Muhammad via Gabriel is effectively contradicted by modern scholarship and common sense. "
The Qur'an was canonised in the reign of Uthman which lasted 653-656. However, Arabic writing had not fully matured as vowels were not recorded. This lead to ambiguity in the text. Over the next few centuries, the script used to express the Qur'an evolved to remove ambiguities. 
- "The oldest manuscripts of the Quran still in existence date from not earlier than about one hundred years after Muhammad's death. "
Sana'a manuscript is one of the oldest extant Qur'anic manuscripts (710–715 by calligraphic dating) and contains many variations from the modern Qur'an. While the variations contain no major differences in doctrine, they do undermine the claim that the Qur'an is completely perfect and unchanging. Alternative editions of the Qur'an were suppressed to create the façade of unity.
Muhammad had an early revelation that said polytheism was true. This was probably motivated by political expediency. He later claimed they were inspired by Satan and are therefore referred to as the Satanic verses. They were expunged from the Qur'an.  This does raise the question that any other religious revelation might have been inspired by Satan.
- ↑ Harald Motzki, The Collection of the Qur’ān. A Reconsideration of Western Views in Light of Recent Methodological Developments, Der Islam, Volume 78, Issue 1 (Jan 2001)
- ↑ Keith E. Small, Textual Criticism and Qur'an Manuscripts, Lexington Books, 22 Apr 2011
- ↑ 3.0 3.1 Harold C. Felder, The Qur'an: Heavenly or Human?
- ↑ 4.0 4.1 4.2 History of the Quran, Wikipedia
- ↑ Myth #1 The Qur‘an is Preserved and Unchanged Revelation from Allah
- ↑ 
- The video that got Nick Gisburnes account deleted This video features less pleasant parts of the Koran and Youtube took it down but after heavy criticism restored it.