It's the Hindu holiday that is in celebration of Lord Rama's return from exile and his defeat over the Deman Ravana (who had kidnapped Rama's wife)... It's called the "Festival of Lights" because we light lamps to signify the triumph of "good -v- evil" (Rama v Ravana). We light the lamps, hold special pujas (prayer services/worship) , decorate, give gifts, light fireworkds, have been feast.. The festival last for 5 days total.
Sikhs (which my husband is) also celebrate Diwali because that is when Guru Har Gobind Ji returned to Amritsar after being inprisoned in Fort Gwalior.
at 8:19 PM on Oct. 11, 2010