Short answers, pulled from the story.
The Sanskrit word Dipavali means a row of lights and was defined by Monier Monier Williams as a compound of dīpa meaning light or lamp and āvali meaning series or row. Early Sanskrit texts like the Padma Purana and Skanda Purana mention this festival between the 7th and 10th centuries.
Emperor Harsha referenced Deepavali in his 7th-century play Nagananda as Dīpapratipadotsava. He described lamps being lit while newly engaged brides and grooms received gifts during the celebration.
Hindus link the festival to legends in the epic Ramayana where Rama returned to Ayodhya after defeating demon king Ravana over fourteen years of exile. Another tradition involves Krishna killing demon Narakasura near present-day Assam which freed 16,000 girls held captive by the evil king.
About 10 billion rupees worth of fireworks were sold to merchants in 2013 according to The Times of India. Confectionery and fireworks are sold in substantial quantities during Diwali with trade organizations forecasting online shopping exceeding 300 billion rupees over the 2017 season.
Barack Obama became first president personally attending Diwali at White House in 2009. He released statement sharing best wishes before visiting India as President and religious significance was officially recognized by United States Congress in 2007.
October 2025 Diwali celebration in Ayodhya Uttar Pradesh broke Guinness World Record largest display oil lamps with 2,617,615 lamps displayed on eve of festival. State of California made Diwali official state holiday October 2025 and Diwali inscribed on UNESCO List Intangible Cultural Heritage becoming 16th Indian tradition receiving global honor.