Indian Railways' official website has a tool that allows users to check their PNR status. The tool requires the passenger to enter their PNR code along with a short verification code and returns the passenger's current PNR status.
PNR stands for Passenger Name Record, and it is the most important and useful piece of information on any passenger's ticket. The PNR not only allows passengers to check the status of the ticket, but Indian Railways also requires that passengers include their PNR code in any official correspondence.
There are three main types of PNR status: confirmed, reserved against cancellation and waiting list. A confirmed PNR status means the passenger is guaranteed a full sleeping berth for her journey. Reserved against cancellation means that the passenger is generally guaranteed a place on the train. However, a reserved against cancellation status usually only entitles the passenger to a seat or a non-sleeping accommodation and not a full sleeping berth.
A wait-listed PNR status is actually one of seven different statuses that correspond to different chances of the passenger's ticket actually becoming confirmed. A general wait list status is the most common type of wait-listed PNR status, and this status also has the highest chance of confirmation. Remote location and roadside wait list statuses have a very low chance of confirmation, but these statuses are very rare. Other wait-listed PNR statuses only apply in unusual circumstances or for certain railway routes.