The Quran clearly states that it was sent down on Laylatul Qadr (97:1). Laylatul Qadr falls on one of the nights of Ramazan. (Sunan Ibn Majah 1644)
In this sense, the month in which the Quran was revealed became a memorable month. This is because the Quran is a book of divine guidance.
A human being is born in this world without any guide on how to lead his life or what he should do. He does not have answers to questions such as: Who am I? What is death? What should I do and not do in this life? What is the purpose of my life?
No person is born with answers to these questions. We have been informed about them in the Quran -- it tells us about the creation plan of God. This shows that the Quran is indeed a big blessing. Without Quranic guidance, one would have to live as a blind person. This is because a person cannot discover the purpose of his life by himself. He does not possess anything by which he can know the truth. Only the Creator has knowledge of this reality. The Creator alone can reveal the creation plan He has in mind on the basis of which he has created and settled man in this world. To inform people of this creation plan, God revealed the Quran through the Prophet Muhammad.
The Quran is a very big blessing. The day when the Quran was revealed was a day of great blessing for mankind. This is why that day was made a memorable day. The Quran began to be revealed in the month of Ramazan.
This is why God made Ramazan a memorable month. He prescribed fasting in this month so that a person would read the Quran more and more, find out the purpose of his life, the secrets of success and reasons for failure. A person is required to search for all truths in the Quran. This is why the Quran is read a lot during Ramazan. It is read as a book and even recited during tarawaih prayers. This is how Ramazan is the month of the Quran.