The Arabic term 'Wahy' means revelation, and within Islam Wahy specifically refers to the revelation of the Holy Qur'an to the Prophet Muhammad. In the year 611 (using the Christian calendar) AD in the grotto of Hira, the angel Jibra'il appeared to Muhammad during the month of Ramadan. That night is known as Lailat-al-Qadr, or "The Night of Destiny." The rest of the words of Allah then followed over a period of 23 years.