The Trilogy is a term used for the three texts that contain the foundations of Islam, the Koran, the Sira and the Hadith. The Sira, Mohammed’s biography and the Hadith, the Traditions of his words and deeds, comprise the Sunna of Mohammed.
The most authoritative version of the Sira is by Ibn Ishaq. There are several versions of Hadith, but the most authoritative and commonly used is by Bukhari.
