Diwali or Deepavali

Diwali or Deepavali, is a major Indian festival, Many legends are associated with Diwali. Today it is celebrated across the globe as the "Festival of Light," where the lights or lamps signify victory of good over the evil within every human being
Diwali is celebrated on the first day of the lunar Kartika month, which comes in the month of October or November.
The word "Divali/Diwali" is a corruption of the Sanskrit word "Deepavali" (also transliterated as "Dipavali"). Deep/dip means "light of the dharma", and avali means "a continuous line". The more literal translation is "rows of clay lamps". The Sanskrit bines array of lights that stands for victory of brightness over darkness.
Deepavali is popularly known as the "festival of lights", the most significant spiritual meaning is "the awareness of the inner light". It marks the victory of good over evil, and uplifting of spiritual darkness. Symbolically it marks the homecoming of goodwill and faith after an absence, as suggested by the Ramayana.
In the day of Diwali, many wear new clothes and share sweets and snacks. Some North Indian business communities start their financial year on Diwali and new account books are opened on this day.
Deepavali is the celebration of Inner Light (spiritual body purification), in particular the knowing of which outshines all darkness (removes all obstacles and dispels all ignorance), awakening the individual to one's true nature, not as the body, but as the unchanging, infinite, immanent and transcendent reality. With the realization of the Atman (soul) comes universal compassion, love, and the awareness of the oneness of all things (higher knowledge). This brings “Ananda” (Inner Joy or Peace).
Diwali celebrates this through festive fireworks, lights, flowers, sharing of sweets, and worship. While the story behind Deepavali varies from region to region, the essence is the same - to rejoice in the Inner Light or the underlying reality of all things

In many parts of India, it is the homecoming of King Rama of Ayodhya after a 14-year exile in the forest. The people of Ayodhya (the capital of his kingdom) welcomed Rama by lighting rows (avali) of lamps (deepa), thus its name, Deepawali, or simply shortened as Diwali. Southern India marks it as the day Lord Krishna defeated the demon Narakasura.
In Jainism it marks the nirvana of Lord Mahavira, which occurred on October 15, 527 BCE. The Sikhs celebrate Diwali for a different reason; on this day, the Sixth Guru, Guru Hargobind Ji, was freed from imprisonment along with 52 Hindu Kings (political prisoners) whom he had arranged to be released as well. after his release he went to Darbar Sahib (golden temple) in the holy city of Amritsar. There, he was greeted by Sikhs and many other people. In happiness they lit candles and diyas to greet the Guru. In India, Diwali is now considered to be a national festival, and the aesthetic aspect of the festival is enjoyed by most Indians regardless of faith.