Facts about AD and BS calender .

The Nepali calendar system, also known as Bikram Sambat (B.S.), is a lunisolar calendar that is based on the cycles of the moon and the sun. It is the official calendar of Nepal and is also used by Nepali-speaking communities in India and other parts of the world. The B.S. calendar is said to have been established by King Vikramaditya of Ujjain in 57 B.C., to commemorate his victory over the Shakas. The calendar has 12 months, each with 29, 30, or 31 days. The months are named after Hindu deities and festivals.

The AD calendar system, also known as the Gregorian calendar, stands for Anno Domini, which is Latin for "Year of our Lord," and is used to number years in the Julian and Gregorian calendars. AD denotes the calendar era after the birth of Jesus Christ. The traditionally accepted year of Christ's birth is labeled AD 1 and the year before is 1 BC. It is the most widely used calendar system in the world. The Gregorian calendar has 12 months, each with 28, 29, 30, or 31 days. The months are named after Roman deities and emperors.

The difference between the B.S. and Gregorian calendar systems is around 57 years. This is because the B.S. calendar is a lunisolar calendar, while the Gregorian calendar is a solar calendar. Lunisolar calendars are based on the cycles of the moon and the sun, while solar calendars are based only on the cycle of the sun. The B.S. calendar is used for both religious and secular purposes in Nepal. It is used to determine the dates of Hindu festivals and holidays, as well as for government and business purposes.