Quran | Allah's words or Mohammed's?

Quran | The different Arabic versions

Muslims say that the Qur'an has been perfectly preserved and that all Qur'ans around the world are absolutely identical.

Which Quran, Mecca or Medina?

The Quran as we know it today is in reality two quite different books. The older Quran was written in Mecca while the later Quran was written in Medina.