Maha Shivaratri is a Hindu festival celebrated annually in reverence of the god Shiva. It is the day Shiva was married to the goddess Parvati. The Maha Shivaratri festival, also popularly known as 'Shivaratri' (spelt as Sivaratri, Shivaratri, Sivarathri, and Shivarathri) or 'Great Night of Shiva', marks the convergence of Shiva and Shakti. Maha Shivaratri is celebrated on the Krishna Paksha Chaturdashi of Hindu calendar month Maagha as per Amavasya-ant month calculation. As per Poornima-ant month calculation, the day is Krishna Paksha Chaturdashi of Hindu calendar month Phalguna which falls in February or March as per the Gregorian calendar. Of the twelve Shivaratris in the year, the Maha Shivarathri is the most holy.
The festival is principally celebrated by offerings of Bael leaves to Shiva, all-day fasting and an all-night-vigil (jagaran). All through the day, devotees chant "Om Namah Shivaya", the sacred mantra of Shiva. Penances are performed in order to gain boons in the practice of Yoga and meditation, in order to reach life's highest good steadily and swiftly. On this day, the planetary positions in the Northern hemisphere act as potent catalysts to help a person raise his or her spiritual energy more easily. The benefits of powerful ancient Sanskrit mantras such as Maha Mrityunjaya Mantra increase greatly on this night.
In Nepal, millions of Hindus attend Shivaratri together from different part of the world at the famous Pashupatinath Temple. Thousands of devotees also attend Mahasivaratri at the famous Shiva Shakti Peetham of Nepal.
In Indo-Caribbean communities throughout the West Indies, thousands of Hindus spend the auspicious night in over 400 temples across the country, offering special jhalls to Lord Shiva.
On Maha Shivaratri, Nishita Kala is the ideal time to observe Shiva Pooja. Nishita Kala celebrates when Lord Shiva appeared on the Earth in the form of Linga. On this day, in all Shiva temples, the most auspicious Lingodbhava Puja is performed.
Example via www.ramdass.org: “Om Namah Sivaya”