The Koran (Qur'an) is the holy scripture of the religion Islam, written by the prophet Muhammad, probably during the sixth or seventh century AD, and likely written over the course of 20-something years, as it was received through the prophecy of Muhammad. The word Koran is from the Arabic word for 'to read' or more specifically, 'to read aloud,' and the word Qur'an or Koran comes to mean something like "The Recitation."
The text is broken up first into Surah and then into Ayah, which function as chapters and verses. The Koran differs in composition from the Judeo-Christian scriptures, because whereas the Bible or the Torah are compilations of several texts, written by several different authors over the course of many years for different purposes, the Koran is a centralized, expository text that obviously understands itself to be a sacred text and often outlines the differences between the Islamic religion and other religions quite clearly, often arguing that until its own existence, humankind had misunderstood the proper meaning of Abrahamic history.
It is critical to note firstly that because of the nature of the text, the most authoritative interpretation of the Koran is its religious meaning in the lives of Muslim people. However, its study can benefit anyone, just as the study of the Bible is informative even to people who don't ascribe to its religious interpretation.
In the text, the names of Allah and Muhammad are honorized through the addition of phrases that are affixed to them (e.g. "Muhammad, holy be his name). Another interesting aspect of the text is that it argues that it be read in Arabic, which poses a problem for people who don't read Arabic. However, many Muslims believe it is okay to study the text in other languages, but they maintain that any study of the Koran in another language is purely academic and the text itself loses something sacred. For this reason, English translations of the text are often regarded not as translations at all, but as commentaries or studies of the text.
To properly understand the history of the Koran, it is important to understand its worldview as an extension of Eastern mysticism, particularly Christian gnosticism and mysticism. This is highly contested, and many Muslims would disagree that Islam ever had roots in Christian thought, but at least some of the theories about Muhammad argue that he would have considered himself a Christian at least at one time in his life. This argument is often supported by exploring the similarities of the Koran's interpretation of the story of Jesus's execution and similar interpretations from Muhammad's time.
The Koran argues directly against the belief that Jesus Christ is God, but it does maintain that Jesus was a prophet of truth and that his story is an important part of our understanding of our relationship with Allah. The text also argues directly against the Jewish faith by contesting the Torah's claim that the Israelite people are God's chosen people. The Koran would maintain that the Arabic people were originally God's chosen people, and that the Jewish people are misled. This is part of what makes the Koran such a divisive book; according to its arguments, the city of Jerusalem is Islamic holy land, and the Israelite claim of the land and of God's blessing is unfounded.
The text is sacred to the Muslim people who have debated its meaning and proper interpretation for more than one thousand years. It is not a book that should be disregarded or interpreted carelessly.
