The Hindu solar calendar is based on the motion of the sun and is used in Northern and Western India to synchronize with the solar year, while the Lunar Amanta calendar ends on the darkest night of the month and is followed in several states including Andhra Pradesh, Gujarat, and Maharashtra. On the other hand, the Lunar Purnimanta calendar ends on the full moon day and is mainly followed in states like Bihar, Chhattisgarh, and Uttar Pradesh