Naraka Chaturdashi

Naraka Chaturdashi (also known as Kali Chaudas, Narak Chaudas, Roop Chaudas, Choti Diwali, Narak Nivaran Chaturdashi or Bhoot Chaturdashi) is an annual Hindu festival that falls on Chaturdashi (the 14th day) of the Krishna Paksha in the Hindu calendar month of Ashvin (according to the amanta tradition) or Kartika (according to the purnimanta tradition). It is the second day of the five-day long festival of Diwali (also known as Deepavali). Hindu literature narrates that the asura (demon) Narakasura was killed on this day by Krishna and Satyabhama.The day is celebrated by early morning religious rituals, and festivities follow on.

Bhoot Chaturdashi is celebrated in Bengal with a lot of love. Fourteen pradips (diyas) are lighted in this occasion.
Meaning in Hinduism
The festival is also called Kali Chaudas, where Kali means dark (eternal) and Chaudas means fourteenth, since it is celebrated on the 14th day of the lunar month of Kārtika or Krishna Paksha. In some regions of India, Kali Chaudas is the day allotted for the worship of Mahakali or Shakti. Kali Chaudas is the day to abolish laziness and evil, which create hell in our life and shine light on life. The god of death, Yama, is also worshipped on this day by lighting a lamp which is believed to protect one from the sufferings of naraka (hell).