In the holy book of Islam, the Quran, a Surah (سورة) is a chapter. The Quran consists of 114 such chapters, with varying lengths, ranging from the shortest, Al-Kawthar (three verses only), to the longest, Al-Baqarah (286 verses).
Each Surah generally deals with a specific topic or group of related issues. These topics may be anything from the histories of prophets and earlier peoples, to theological concepts, ethical advice, and ordinances for different areas of life. The Surahs are not ordered chronologically according to revelation order but chiefly by size, with the longer ones tending to appear near the beginning of the Quran and the shorter ones towards the end. Every Surah, with the exception of At-Tawbah, starts with the words "Bismillah ir-Rahman ir-Rahim" (In the name of Allah, the Most Gracious, the Most Merciful), which is an invocation and a division marker between the chapters. Knowledge of the individual Surahs and context is important for an insightful understanding of the message of the Quran.