Wikipedia
The Cow or Sūrat al-Baqarah (, "The Cow") is the second and longest chapter ( Surah) of the Qur'an. It is a Medinan sura (revealed to Muhammad when he was at Medina), with the exception of verse 281 which Muslims believe was revealed during The Farewell Pilgrimage. It is also considered to be one of the first chapters revealed after the Hijra from Mecca to Medina. The chapter comprises 286 verses ( ayat) according to the division of Ali, the most widely accepted count among all Muslim denominations, and includes the single longest verse in the Qur'an (2:282). The surah's name references verses 66–72 which recall the story of a heifer sacrificed by the Israelites.
Surah al-Baqarah enjoins fasting on the believer during the month of Ramadan.