2. Al-Baqarah (the Cow)
The Cow or S?rah al-Baqarah (Arabic: ???? ???????, "The Cow") is the second and longest chapter (Surah) of the Qur'an. It consists of 286 verses, 6201 words and 25500 letters (Ibn Kathir). It is a Mediniite surah, that is to say that it was revealed at Medina after the Hijrah, with the exception of a few verses which Muslims believe was revealed during the last Hajj of Muhammad The Farewell Pilgrimage.
This is the longest Surah in the Quran. It was the first Surah to be revealed at Medina, but different verses were revealed at different times, covering quite a long period so much so that the verses with regard to riba (interest or usury) were revealed in the final days of Muhammad, after the conquest of Makkah (Maariful Quran).