This year, the primary festivities are set to kick off on October 20 and will span the traditional five-day period.

The illumination during Diwali holds both mythical and spiritual significance.

Diwali celebrations are marked by lighting up homes and public areas, spectacular fireworks, cultural performances, and the exchange of food and gifts.

Diwali festivities include decorating public spaces and homes with lights, fireworks displays, cultural activities and the sharing of food and gifts. Source: AAP / Tracey Nearmy

Hindus, Jains, Sikhs and some Buddhists celebrate the spiritual victory of good over evil, light over darkness, and knowledge over ignorance.

What is the Hindu story of Diwali?

While there are different stories about the festival’s origins, even Australians who aren’t religious still celebrate Diwali, according to Professor Ian Woolford, a lecturer in Hindi language at La Trobe University.

In Nepal, the festival is known as Tihar and, along with worshipping Hindu gods and goddesses, animals such as crows, dogs and cows are honoured with gifts of food and adorned with garlands.

Diwali is one of the most important festivals in India. Source: AAP / EPA

Melbourne Diwali Festival organiser Arun Sharma told SBS News in a previous interview that the ritual of using lights, also known as diyas, can be an opportunity to quietly meditate, concentrate on this light, and illuminate your soul.

Lights and firecracker displays can also be thought of as an expression of gratitude to the heavens for the attainment of health, wealth, knowledge, peace and prosperity.

Diwali, also known as the ‘festival of lights’, is a celebration of ancient king Rama’s return to his rightful place as ruler of the kingdom of Ayodhya, and represents the victory of light over darkness and good over evil. Source: Getty / Lisa Maree Williams

What happens during Diwali

Day 4: The next day, Nutan Varsh, is celebrated as New Year’s Day in the state of Gujarat on India’s western coast.

People light firecrackers on Diwali night, symbolising the triumph of light over darkness.

Friends and family exchange gifts and sweets and they also create Annakut — mountains of food arranged in large tiers or shapes representing India’s Mount Govardhan.