Charak Puja is counted among the most valued festivals in rural Bengal. To the local residents in the city of Kolkata (Calcutta) this festival is known as Batri Charak. This grand festival is celebrated with lot of pomp and glory in the remote areas of West Bengal state by the members of different agricultural communities. This is one of the most fascinating folk festivals of the southern belt of West Bengal and Bangladesh. Charak Puja is also called `Nil Puja`. The puja is celebrated by the Hindus on the last day of Chaitra or on the day of the Chaitra Sonkranti.

Charak Puja is dedicated to the Goddess Shakti and the Lord Shiva, and people who take part in this puja are required to undergo a prolong fast. Generally during such fasts the devotees are not permitted to have food from early morning till evening and therefore, be subjected to physical pain. However, at the time of Charak Puja, those who take up fasting, are allowed only to have some fruits and are required to pray the Lord Shiva for his divine blessings.

This festival or puja is devoted solely to penance and it is, thus, quite unique in the huge list of several Bengali festivals. The group of women and men who take up this time bound ritual or `Brata`, are subject to practice a month long fasting which begins from sunrise and continues till sunset. The team which arrange for the festival, travel to different villages to gather necessary items like paddy, sugar, oil, money, salt, honey and a list of other items along with the arranged cosmetics like Narod, Shiva and Parvati. The cosmetic Shiva is known as `Jal Katha` or `Nil Pagol` locally. On the auspicious midnight of the Songkranti, the devotees gather in order to worship the God and after Puja is completed, the `Prosad` is distributed among the devotees.

On the auspicious day of the `Gajan` or the `Charak`, bamboo stages are constructed over bamboo poles, and its height ranges from ten to fifteen feet and then follows a very fascinating incident. After the proper execution of a month long fasting and meditation, the devotees climb up to the high bamboo stage and jump or just through themselves forward. They fall on the ground which is completely filled with thorns, glass, knives and a list of other devious weapons. To the utter surprise of all, they are not hurt. It is believed that the divine blessing of the God helps them stay safe from being hurt by such difficulties. There are also other ways in which the devotees demonstrate the blessings of the Lord over them. They just impale some parts of their body and do not feel a little pain. The Charak Puja thus demonstrates a blind faith of the devotees and also shows their strong will to jovially accept penance in order to get salvation.

The Charak Puja is, thus, celebrated with lots of hardships which include regular fasting and in the end the devotees throw themselves on the ground from the bamboo stages where several devious weapons like broken glass, knives, etc are kept. Thus is not the end, some also hurt their body parts to show the miracle of God. In this process they express their deep faith on their Gods and goddesses. These devotees are famously called Charkia. Normally ten to twelve members take part in this ritual together. The chief performer of this Puja is called the Deoboinshi. Charak are of two types; one is known as the Chak Charak and the other is called the Chila Charak.

It is believed by the devotees that the Charak Puja will bring in prosperity by wiping out the sufferings and sorrow of the last year. This is celebrated mainly to please the Lord Shiva, the renowned `Debadideb` of the Hindus. Even if the festival is held on the mid night of Chaitra Songkranti, the preparation for the same normally kicks off before one month of the day.