It symbolises the spiritual victory of Dharma over Adharma, light over darkness, good over evil, and knowledge over ignorance. Diwali is celebrated during the Hindu lunisolar months of Ashvin (according to the amanta tradition) and Kārtika – between around mid-September and mid-November. The celebrations generally last five or six days.
Diwali is a festival of light in Hinduism/India:
https://en.wikipedia.org/wiki/Diwali
Wow, knowledge over ignorance and then you have dipshits like OOP posting on that day.