Although modern-day Bali operates using the familiar Roman Calendar that most people are used to, with 365 days in a year, there are two other calendars that also play an important role in the lives of the Balinese.
The most important calendar for the Balinese is one using a 210-day cycle. Although many people would not be able to tell you exactly when their birthday is as a date from the Roman calendar, they would certainly know when their oton (Balinese birthday) is. Also this calendar is used to determine the dates of the many odalan (temple anniversary ceremonies) as well as the many special festival days that are celebrated island-wide in Bali.
There is also a third Lunar, or Saka Calendar that operates to determine particular events in the lives of the Balinese, especially for the farmers in the rural areas of Bali. This calendar is determined by the phases of the moon, the most important days being purnama (full moon) & tilem (new moon). Nyepi (Balinese New Year) is also determined using this calendar, the eve of Nyepi falling on the night of the new moon whenever it occurs around March/April each year.