Indians are celebrating Diwali as bright earthen oil lamps and colourful lights light up homes and streets across the country to mark the Hindu festival that symbolises the victory of light over darkness.

Diwali is the most important festival of the year in India and for Hindus in particular. It is celebrated across faiths in the world’s most populous nation and the diaspora.

Over five days starting on Thursday, people are taking part in fireworks displays, feasts and prayer. Diwali is derived from the word “Deepavali”, which means “a row of lights”. Celebrants light rows of traditional clay oil lamps outside their homes to symbolise the victory of light over darkness and knowledge over ignorance.

The dates of the festival are based on the Hindu lunar calendar and typically fall in late October and early November.

The festival brings with it a number of unique traditions that vary by region. What all celebrations have in common are the lights, fireworks, feasting new clothes and praying.

In southern India, many have an early morning warm oil bath to symbolise bathing in the holy river Ganges as a form of physical and spiritual purification.

In the north, worshipping the goddess Lakshmi, who symbolises wealth and prosperity, is the norm.

Gambling is a popular tradition because of a belief that whoever gambles during Diwali will prosper throughout the year. Many people buy gold on the first day of Diwali, known as Dhanteras – an act they believe will bring them good luck.

Setting off firecrackers is a cherished tradition as is exchanging sweets and gifts among friends and family. Diwali celebrations typically feature rangoli, which are geometric, floral patterns drawn on the floor using colourful powders.

This year, several northern Indian states, including the capital, New Delhi, are instituting partial or total fireworks bans to combat rising pollution levels during Diwali.