In the context of train ticket booking in Indian Railways, NC stands for "No Choice". It means that the passengers preferred berth choice was not available, and they were allotted a different berth based on the availability of seats. For example, if a passenger booked a window seat but did not get it, the berth number on their ticket would have "NC" written next to it. While NC might not be the preferred choice for passengers, it is still a valid ticket and allows them to travel on the train. Passengers can check their ticket status online on the Indian Railways website or through the mobile app to know if their berth preference has been confirmed or not.