1. Also known as Deepavali, it means 'Festival of Lights' and it's the most fun festival in the Hindu religion. This year it's on November 11.
2. The festival celebrates the victory of good over evil, light over darkness and knowledge over ignorance,
3. It's marked with fireworks, lamps and candles. Before Diwali night people clean and renovate their homes.
4. There is usually family worship in homes followed by gift-giving and a feast. Pre-Diwali shopping is a big thing, like at Christmas.
5. In India's capital Delhi and other big cities there is so much smoke from fireworks that the corpses of asphyxiated birds are seen in the streets the next day.
6. Traditionally people light Diwali 'diyas', small clay oil lamps with cotton wicks. In recent years they've been turning to battery-operated ones and diya-makers are going out of business.
7. One of the biggest celebrations of Diwali in the UK is in Leicester, whose Golden Mile on Belgrave Road is a giant ribbon of light.
8. In India it can be a dangerous time because of the numbers of naked flames around. Last year there were 220 accidents in Delhi. In Faridabad a fire broke out in a firework market and gutted 230 shops.
9. Many Hindus keep Diwali to honour the return of the god Ram, his wife Sita and brother Lakshmana from exile, but local customs vary. For Sikhs it's about Bandi Choorh Divas, when Guru Har Gobind escaped from Gwalior and arrived at the Golden Temple in Amritsar. For Jains it's when Mahavira, the last of the Tirthankar of this era, attained Nirvana. It is a usefully comprehensive festival.
10. Because November 11 is Remembrance Day and a very, very big thing in London, it was celebrated a month earlier there, on October 11. There was a big festival in Trafalgar Square with lots of South Indian cuisine available. It commemorated the role the Indian sub-continent played in World War I.
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