Holidays
India's national holidays for any year — a short, fixed list, since most religious and regional observances are deliberately left to individual states.
India officially designates just three "national holidays" observed uniformly across every state: Republic Day, Independence Day, and Gandhi Jayanti. That's a deliberately short list for a country of India's religious and cultural diversity — nearly everything else (Diwali, Eid, Holi, Christmas, and dozens of regional and state-specific observances) is classified as a "gazetted holiday," officially declared each year but not uniform nationwide.
Each state government publishes its own list of gazetted and "restricted" holidays annually, reflecting the dominant religious and cultural makeup of that specific state — which is why an employee in Kerala and one in Punjab can have almost entirely different holiday calendars for the same year, aside from these three shared national dates. See Diwali Dates and the Islamic holiday estimator for two of the most widely observed gazetted holidays specifically.
Related
One of India's most widely observed gazetted holidays.
Another major gazetted holiday observed across much of India.
A very differently structured national holiday calendar.