Question
What year is it according to the Hindu Lunar Calendar?
Answer
First of all, there isn't really such a thing as "the Hindu calendar". Most Hindu calendars are based on the system described in the Surya Siddhanta, an ancient astronomical treatise, but then subsequently a lot of regional variations on the Surya Siddhanta system developed. Still, most Hindu calendars are lunisolar, in the sense that they have lunar months and sidereal solar days.
Now as far as the zero year goes, different Hindu calendar systems have different zero years, but these are the most prominent:
3102 BC - This is the zero year of the so-called Yudhishthira Samvat calendar, believed to have originated with the king Yudhisthira (although I'm not sure if Yudhisthira's involvement is mentioned in scriptures). It is the year when Krishna departed the Earth (which I discuss here), and for that reason it is also the start of the Kali Yuga. In religious contexts, this is the zero year that's most often used. For instance, people might say "Ramanujacharya was born on such-and-such year of the Kali Yuga."
56 BC - This is the zero year of the Vikram Samvat, created by the king Vikramaditya to commemorate his victory against the Scythians. This is the calendar commonly used in North India.
78 AD - This is the zero year of the Shalivahana Samvat calendar, AKA, the Saka calendar, instituted by the king Gautamiputra Satakarni to celebrate his own victory against the Scythians. (It looks like nothing much changed in a hundred years!) This has been adopted as the national calendar of India.
Notwithstanding all this, if you were to walk up to an educated Hindu and ask him what the zero year of the Hindu calendar is, they would most likely say 3102 BC.
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