Hindus relate many things to this celebration, such as the returning of Rama after his exile or the death of the demon Narakasura by Lord Sri Krishna.
It is celebrated in many ways in the different regions of India, usually with pujas, firecrackers, decorating the house by setting oil lamps and candles, at times also rangoli decorations, and eating sweets and such.
In the last couple of years, i have come so close to India that now it is a very dear part of myself. So i made my (very) little Diwali celebration. And made this photoshot of my Diawli candle.