When you book your reservation ticket through irctc.co.in or from ticket windows, it is given an PNR number (shown in the circle of image). You just need to enter this ten digit PNR number in empty box given on this page and hit check pnr status button. You will come to know about your pnr enquiry and whether your ticket is confirmed or not. You can also know which coach your seat is available.
Enter your 10 digits PNR number Without Hyphen “-”
In many cases your ticket is not confirmed or you might see RAC or WL in your pnr status. The meaning of WL is waiting list, while RAC means reservation against cancellation. It will also show you current position of your ticket status, and after how many number you will find your ticket confirmed.