Tamil Calendar, a differential form of the old Hindu calendar, is based on the sidereal year system. It starts in the middle of April and has twelve months with a varying number of days. A maximum of 32 days are possible in a month. Same as any other calendar, the Tamil calendar also has a seven-day week. Based on the five Jovian periods, each year in the calendar takes a different name and follows a 60-year cycle. The 12 months (in the order of January to December) are Thai, Maasi, Panguni, Chithirai, Vaikasi, Aani,
Aadi, Aavani, Purattasi, Aippasi, Karthikai and Markazhi. The Tamil New Year falls in the month of Chithirai.
