Pradosh Kaal is a period considered very important in many Hindu festivals. It is a bimonthly occasion on the thirteenth day of every fortnight in the Hindu calendar. The auspicious three-hour period 1.5 hours before and after sunset is considered as the most important time for worshiping Lord Shiva. During this time, Lord Shiva is worshipped by his devotees, and observing fast on the day of Pradosh fulfills all the wishes of the devotees and bestows wealth, good health, and happiness. The Pradosh worship is done in the evening twilight or sandhya kala, and the performance of the vrata involves a fast followed by a vigil. The Pradosh vrat can be conducted by every human being irrespective of age and gender. The word Pradosh Vrat in Hindi means Vrat related to the first part of the night or the evening.

In summary, Pradosh Kaal is a period of three hours before and after sunset that is considered very important for worshiping Lord Shiva. It is observed twice a month on the thirteenth day of every fortnight in the Hindu calendar, and observing fast on this day fulfills the wishes of the devotees.