Hindu Holidays and Festivals are diverse and celebrate everything from ancient religion and honoring deities, to the change of seasons and commemorating events. Many of the Hindu festivals are celebrated worldwide while some are celebrated in specific regions.
The dates for the holidays go by the Hindu lunisolar calendar, which is different from the gregorian calendar so the dates vary from year to year.
Deity celebrations: Shivaratri, Ramanavami, Krishna Janmashtami, Ganesha Chaturti, Navaratri
Seasonal Celebrations: Holi and Makara Sandranti aka Uttarayana or Pongal
Life celebrations: Raksha Gandhan and Diwali/Deepavali