Happy Diwali! Here's what you need to know about the Hindu festival of lights on Thursday

Diwali, one of the biggest festivals in India, begins Thursday, Nov. 4.

Celebrated during the Hindu month of Kartika, the festival commemorates the triumph of good over evil, with glistening lights and delicious food. It is celebrated around the world by followers of the Hindu faith and beyond.

Here is what you need to know about Diwali.

When is Diwali celebrated?

Diwali rituals and preparations take place over five days between mid-October and mid-November. Since the holiday is celebrated by the lunar calendar instead of the Gregorian, the date varies year-by-year.

Whare are Diwali's origins?

The true origins of Diwali are still debated. The festival was first mentioned in Sanskrit scriptures in the second half of the first millennium AD. The holiday's themes of good vs. evil and knowledge vs. ignorance first appeared in the Katha Upanishad, a Hindu religious text, in first millennium B.C. Although the holiday's roots are in Hinduism, Diwali has grown in popularity over the centuries and is now celebrated by Indians of different religious creeds, including Buddhists and Sikhs.

What is Diwali's religious significance?

Diwali marks the return of the Hindu deity Rama to his kingdom after defeating the demon king Ravana. The holiday also marks the deity Krishna's victory over Narakasura, the demon of ignorance, according to Hinduism Today. The triumphs of these gods are at the root of Diwali, with participants celebrating Rama's victory of good over evil and Krishna's victory of knowledge over ignorance.

How is Diwali celebrated?

On Diwali night, participants dress up in colorful clothing and light oil-wick lamps, filling their homes with bright light. Communities will also share tasty treats, light fireworks and pray to the deities. "If you rolled a bit of Christmas, New Year's Eve and the Fourth of July all into one, then catered the affair with mountains of sweets and savory snacks, you would have a taste of what it means to celebrate Diwali," writes Hinduism Today.

Why is it the 'festival of lights?

Light is a major symbol in Hindu culture, signifying knowledge and consciousness. Hindus incorporate light into Diwali by lighting lamps to keep darkness away from their hearts and to embrace knowledge and goodness, according to National Geographic. Lighting lamps is also done by Hindu followers to invite Lakshmi into their homes. These bright lamps helped make Diwali known as the "festival of lights" across the world.