Deepavali, the festival of lights, is held throughout India. In Kerala, this is celebrated only by Hindus. It falls on the preceding day of the New Moon in the Malayalam month Thulam (October-November). It is celebrated in commemoration of the destruction of the demon called Narakasura by Lord Krishna. As Lord Krishna killed Narakasura on the Chaturdasi day (the fourteenth lunar day) it is also known as Narakachaturdasi.

Before sunrise, all in the house have their oil bath and put on new cloths. Sweets are then served followed by bursting of crackers. The word 'Deepavali' means an array of lights. The people of Dwaraka greeted Lord Krishna with illumination and rejoicing in honour of his victory over Narakasura. The darkness of the Chaturdasi night compelled them to use many lamps on the occasion, and subsequently the illumination became a part of this celebration.

It is the practice in south India to consume a preparation of dry ginger and jaggery soon after the oil bath on the Deepavali day. Dry ginger and jaggery form the Nivedya (offering) for Dhanwantari, the great exponent of Ayurveda. The Dhanwantari Jayanthi falls on the eve of Deepavali.  The separate observance of this day had come to an end and enjoying the preparation of dry ginger and jaggery fallen to succeeding day namely Deepavali.

Deepavali may have deeper significance than what is popularly believed. At the time of the festival the sun is in the house of Thulam (Libra ie. the scales) which signifies commerce, and hence the association of Deepavali with merchants and the Goddess of wealth. The darkness and light symbolise ignorance and knowledge respectively.

As the light dispels darkness, ignorance is replaced by knowledge. There is a prayer in the Upanishat. 'Thamaso ma Jyothirgamaya' ie. "carry us from the darkness to light" some people are of the opinion that Deepavali, the festival of lights, symbolises this prayer.