Maha Shivratri or Maha Sivaratri or Shivaratri or Sivaratri (Night of Shiva or "Great Night of Shiva") is a festival celebrated every year on the 13th night/14th day in the Krishna Paksha (waning moon) of the month of Maagha (as per Shalivahana or Gujarati Vikrama) or Phalguna (as per Vikrama) in the Hindu Calendar (that is, the night before and day of the new moon). The festival is principally celebrated by offerings of Bael (Bilva) leaves to the Lord Shiva, all day fasting and an all night long vigil. Ganja is traditionally used as an offering for Lord Shiva and his followers.