Due to the age and diversity of Hindu culture, there are several various calendars in use. Some of these are lunar and others solar. I will attempt to explain one of each type here. They also have various starting points from different Yugas [ages or eras].
Yugas:
The Hindu civil calendar is solar and officially numbers years from the beginning of the Sata Yuga.
Months:
Of the lunar calendars, the amânta system common in southern India begins the month on the new moon, and the pûrnimânta system common in northern begins the month on the full moon. The days of each moon are named the same from new to full as from full to new.
Moon Days:
The fifteenth is also called Suklapaksha purnimã [Full Moon] or krsnapaksa amãvãsyã [New Moon].
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